Fiero brake system info

Warning! Be aware that Asbestos is still used in many brake products. Avoid buying products that contain asbestos.
Products that are “asbestos free” may still contain hazardous materials. Avoid any cleaning method that puts brake (or clutch) dust into the air. Don’t vacuum clean it either. Most vacuum cleaners are not safe for this work and could contaminate a huge area with hazardous dust.

Cleaning & Lubrication

Warning! Use Only high temperature silicone or synthetic grease made specifically for brake work. Never use petroleum based products. Oil based grease can damage brake parts in a number of ways. Don’t get sloppy with the grease! A little goes a long way.
Don’t use petroleum-based solvents or Gasoline to clean brake parts! These will leave a residue on them that will cause problems. Use one of the commercial brake cleaning products,
“Simple Green” and water, “Citri Solv” and water, or alcohol.
Did he say soap and water? Yup. Soap and water for cleaning a big item like a rotor is hard to beat. It’s cheap and doesn’t stink. It’s not nearly as toxic as commercial brake cleaners. I’ve found I can clean the coating off new rotors much faster in the kitchen sink than with any other method. The only thing to watch out for is your soap choice. The two I mentioned above won’t leave any residue. Others will work as well. Most Dish soap should be fine.
Out on the wheels, anywhere 2 parts of the brake system touch must be clean.
Dirt and corrosion in contact points are major sources of brake problems. Some areas also need to be greased. Make sure you only grease the areas that are supposed to be greased. If you botch this, you hope all that happens is some
annoying noise. Binding parts can cause noise, warped rotors, worn pads, brake fade, brake failure, and reduced gas mileage.
Whenever the caliper is off the bracket, the boltholes and all the bracket contact areas must be checked cleaned and greased as needed. Failure to do this is a major cause of brake problems. It’s even more important in high salt areas that promote corrosion of exposed parts. (In those areas the brakes should be cleaned and greased at least once a year to prevent problems.)
When you grease the slide bolts, coat the entire inside of the boltholes in the caliper. Don’t forget to grease the contact points where the caliper and inner pad contact the bracket. The grease provides lubricant but mainly it prevents rust buildup that can bind the caliper and pads. You only need a thin film of grease on the bracket areas. If you use too much, it can get on the rotor or pads and cause trouble.

Brake Pedal

The brake pedal hardware needs little maintenance other than an occasional dab of grease in the MC push rod eye. Here’s some stuff about the pedal if you need it. It tells you what to lube and what not to. Also includes the measured pedal ratio.

Master Cylinder

Here’s how the MC and it’s Quick Take-up valve works Check the gasket on the MC lid every time you open it. If the gasket shows any damage at all replace it. You should also consider flushing the brake system because any damage to this gasket usually means you have really wet brake fluid.
For some time now service people have been told to open bleeder screws when compressing the calipers on ABS equipped cars. You need to do this for ALL GM vehicles with “Step Bore” AKA “Quick Take-up” master cylinders. (Failing to do this on ABS can cause errors in the ABS computer.) All stock Fieros have this type master cylinder.
Like ABS, the Quick Take-up master cylinder has several very small passages inside it that could be blocked by debris stirred up by caliper compression. The Flow Valve above the primary (rear) piston on the MC is especially susceptible to dirt problems. If you can’t open the bleeder screws, compress the caliper very slowly to avoid plugging the passages in the flow valve.
When cleaning out the tank during a fluid change avoid stirring up dirt. Suck out the fluid slowly from the bottom of the MC opening. This will help draw in loose material on top of the MC. Once the fluid is drained, wipe out the dirt in the bottom of the tank with a soft rag that will trap the dirt so it can’t fall into the MC opening.
NOTE! Never poke anything into openings in the MC. Most openings are calibrated passages that are easily damaged or plugged by foreign objects.
Damaged openings could cut into seals and cause brake failure.

Power Brake Filter

Older models of Fiero have a filter in the booster vacuum line. If the filter is blocked it will cause problems with the brake booster. This filter, or an equivalent to it, can be found in the MotorMite Master Catalog. It may even be on the shelf in some stores.
The filter serves 2 purposes. It will prevent crap from being sucked down the line into the engine. (Especially if the line is unplugged from the booster with the engine running.) It also prevents engine dirt getting to the booster.
Is the Filter needed? Some people would say no. If you have one you should probably replace it every couple years. If you don’t have one, I’d consider adding it. The filter is cheap. It’s easy if a bit awkward to install. You just cut the rubber line, insert the filter, and clamp the line. The purpose of the filter is to keep crud sucked in thru the booster and loose rust inside the steel line vacuum line from reaching your engine. It’s not to protect the booster. If you install one, make sure it won’t melt.

Bleeding

The angle at which the Fiero Master Cylinder is mounted can make the system hard to bleed. If you are having trouble getting all the air out then try parking the car nose down or jacking the rear until the MC is level. This is a common problem in GM cars with tipped master cylinders.
The mounting angle makes proper bench bleeding of master cylinders even more important than normal. Leave the bench bleeding stuff on the MC until the last possible second to prevent air from entering. (Pinch/plug the bleeder lines so you can carry the MC with the cover on.)
More about why the MC is such a pain.

Bleed Sequence

The preferred wheel sequence for bleeding is Right Rear, Left Rear, Right Front, and Left Front.

Bleeder Removal & Repair

If the Bleeders open, check them for any damage. Replace them while you have the chance.
If they won’t open you’re in for a fun time. Not! In cast iron calipers, you can often heat the caliper to free a stuck bleeder screw. This is difficult on aluminum for two reasons.

• Aluminum conducts heat much faster than cast iron. This can make it impossible to get enough heat to release the screw without damaging the caliper. You could need to rebuild the caliper if you try this.
• The steel bleeder and Aluminum often develop galvanic corrosion similar to marine applications. This form of corrosion can effectively weld the 2 parts together and make them impossible to separate by any method.

More often than not, the screw will break off. When that happens, you are going to have to drill it out and install an over size bleeder or a repair bleeder.
An over size bleeder screw works well if you can get a good seat for the seal.
That can be much trickier than you think. (As big as the stock bleeders are, there may not be oversize ones to replace them.)
A repair bleeder has an insert for the caliper and a new screw. You drill and tap the hole, install the insert and new screw. Then you treat the caliper as normal. These cost more than an over size bleeder but they save you having to fight with the bleeder seat. You also get new threads in the calipers that are unlikely to strip. Don’t forget to put some thread locker, preferably the permanent kind, on the outside of the insert before you install it. Don’t get any thread lock on the bleeder or inside the insert.
Two sources of bleeder repair kits are Thexton and MotorMite. Since you are making a new bleeder hole, it doesn’t matter that they aren’t metric.

Preventing bleeder seizure

Here are a few things you can do to prevent the bleeder screws from seizing in the caliper. (Do this any time a bleeder is opened or replaced.)

• Before you flush or bleed… Remove the bleeder and coat it with anti-seize compound. Coat all the bleeder threads. Screw it in finger tight then wipe away any excess. (Don’t do this to bleeders that came with thread coating on them.Some of the “one man” bleeder screws are like that.) For best results do this before you install new calipers. (or at least before you start bleeding new ones.)
• Don’t get sloppy with the compound or you could contaminate the brake fluid.
• Some people say they have good luck with Teflon tape on the bleeder threads. (Tape also helps seal loose screws for easier bleeding with a vacuum tool.)

• After bleeding blow out the bleeder as best you can. This gets the excess fluid out to prevent corrosion.
• CAP the bleeder to keep out dirt and water. Part of the cause of bleeder freeze is crud getting down the bleeder and corroding the hole from the inside. If you have “one man” bleeders installed the caps will prevent damage to the check valve and spring found in this type screw. Any small plastic or rubber cap that stays tight will do.

One solution for bleeder caps is to harvest some on one of your trips to a scrap yard. (Look for Grand Am and similar GM cars. Those front bleeders came capped from the factory.) Some cars have captive caps with little leashes that keep them from getting lost while you are working on them.

Brake Fluid

The DOT 3 brake fluid has an affection for water and needs periodic changing.
Just how often depends on a few things but every 2 years is probably a good maximum.
I’m not going to cover the specifics of changing the fluid here. Most people’s bleeder screws are frozen so this isn’t likely to happen on most cars. Just keep in mind that if you think you have brake fade problems then your first step should be a complete fluid change. (Ok, I caved. Flushing tips are farther down the page.)
The fluid should always be changed anytime a caliper or MC is removed or replaced. Crud in the old fluid can ruin new parts in short order. Crud that was stuck inside of parts can be knocked loose. Changing the fluid will help get the junk out. (It usually takes me a quart, sometimes more, to flush all the junk from the system.)
A thing I like to do is to purge the lines with fresh fluid before installing new calipers. This gets all the garbage out of the lines before the new parts are on so that none of it ends up in the new part. If I’m only changing an MC I bleed until I get new fluid from each wheel. That gets rid of the majority of crud.
No, I don’t recommend Silicone fluids on street driven cars. DOT3 will work just fine in a system that is working properly. Silicone “DOT5″ fluids have problems of their own. For best results use one of the newer high temperature DOT3 formulas.
For much more information about this, read the Brake Fluid article. It cover’s issues about fluid choices in detail.

Caliper Hardware

Contrary to popular belief the slide bolts used in 84-87 calipers DO NOT carry significant brake load during stopping. The purpose of the slide bolts is to guide the caliper and keep it floating smoothly in the bracket. The load from the pads is transmitted to the caliper bracket by other paths. (This is true of all GM calipers with this style slide bolt.)
The inner pad transfers load to the caliper bracket directly. This prevents side loading of the piston that could jam the caliper or cause a leak. Remember to test fit the inner pad in the bracket. Make sure it’s not binding. If it is, scrape off the paint of the top and bottom edge of the pad backing plate and retry it.
The paint can be thick enough to bind the pad.
The outer pad load is transmitted through the caliper to stops on the bracket above and below the caliper. At rest the caliper floats free between the stops, resting on the rubber bushings in the slide bolt holes.

Rebuilding

I’ve been asked many times about rebuilding brake parts. Here’s my list.
Before you even consider rebuilding the calipers, make sure the bleeder screws will open. If they will not open, or break off, then forget it.

Front

These are easy to rebuild. As long as the pistons are in good shape then go for it.
BTW, The Phenolic pistons are actually better than steel ones. They provide a better sealing surface and don’t conduct heat like steel. If you have these, don’t replace them unless they are damaged.

Rear

I do not recommend people do these unless they have rebuilt allot of calipers.
There are a number of things to go wrong here, and most of them won’t show up until later. I’m told you can get these rebuilt from one of the chain parts stores for about $30 each.
Note! There is a seal inside the piston that cannot be repaired. If the pistons are leaking fluid thru the vent plug/hole then the piston must be replaced.

Master Cylinder

I’ve been looking into this one for a while. The little information I can find of the automotive trade publications indicates that aluminum master cylinders should not be rebuilt. There are 3 main reasons given:

• It’s extremely difficult to obtain the correct surface finish with the equipment available to the public. Improper surface finish will ruin the seals in short order.
• Most, if not all, Aluminum master cylinders have anodized coatings that cannot be duplicated without very expensive equipment. This coating prevents corrosion of the MC bore(s). Any honing of such MC’s will destroy these coatings.
• With Step Bore MC’s you’ve also got to mess with the flow valve in the primary circuit. The smallest problem with this valve can leave you with poor or no brakes.

System Flushing tips

Normally, I’d flush when I’m replacing a Master Cylinder or Caliper to prevent damage to the new parts. Flushing a system without rebuilding or replacing anything is a pain but it is doable. You won’t get all the old fluid but you’ll get enough to make a difference and it’s usually worth the effort. In an OE Fiero, the front brakes will benefit more than the rear.
Always flush the MC and brake lines any time a caliper is disconnected. If you are replacing the flex lines, take the caliper off and dump the old fluid out. If you are replacing a caliper, purge the lines before connecting the new one. It is allot easier to fill an empty caliper than flush it. It also protects new parts from residual trash.
You do have to be careful. If your system is in bad shape, you can shake up trash that can bind a piston or eat a seal. Of course, if your system is in bad shape you probably can’t open the bleeder screws anyway….

Will flushing get all the old fluid?

No. You’ll always leave some behind unless you are rebuilding the system. The new fluid will be degraded some by the old fluid but it is still worth the effort to flush the system. (Fiero’s OE rear brakes, like most OE rear disks, are difficult to flush even on a good day.)
The new fluid will bring in fresh corrosion inhibitors and lubricants. This will prevent damage from remaining moisture. With each flush, you’ll preserve life of brake components. (This is especially true of vehicles with ABS. A failed ABS unit can cost hundreds of dollars to replace.)
If you use a fluid with a high Wet boiling temperature, like you should be, then any moisture that wasn’t flushed won’t be as much of a problem.
For street applications, if the system has never been flushed before, consider doing an extra flush in 6 to 9 months. This “short” interval will help draw out the old fluid and eliminate it. After that you should be allot closer to fluid operating on its dry boiling temperature. (Racers should be rebuilding/upgrading the system, work that will include a total fluid flush.)
You have to be very careful if you flush an ABS system. If you do this wrong, you can cause the ABS computer to shut down the system. I mention this because I know some of you have other cars with this installed. Make sure you follow manufacturer’s bleeding instructions to the letter.

How Much Fluid Will I need?

Expect to use a quart or more for each axle depending on just how you do them.
The rear axle will use less fluid if you drain and refill the calipers instead of trying to flush them clean. These things hold much more fluid than the front.

Master Cylinder

Pull the old crud out with a “turkey baster” and use a CLEAN soft rag to carefully wipe up the bottom of the tank. (Select a rag that won’t dump lint in the MC!) Don’t try to pull every drop from the MC openings! You don’t want air to get in there.
When you pour in the new fluid, go slowly and don’t pour directly into the MC openings in the tank bottom. Again, this is to avoid getting air into the MC.

Front

Open the bleeders then compress the front pistons. This will force out most of the fluid in them. Leave the bleeders open until new fluid flows from them. (I usually just gravity bleed them but if you are in a hurry use a vacuum set.)
Close the bleeders and slowly pump up the calipers with the new fluid.
This should remove the bulk of old fluid but if the old fluid was really trashed or you are planning to race then do this a few more times.

Rear

Fiero OE Rear calipers are difficult to flush. Even with the pistons compressed,
they will hold significant fluid. Since rear calipers don’t usually receive the heat that front ones get, you’ll have to decide just how much effort you want to spend on them. If the fluid were old, especially more than a couple years, I’d do it. (Don’t take off the banjo bolt unless you really have to. You’ll have to replace the seals and the thing strips very easily.)
You can try using the same method as the front but I think you’d have to pump them out several times to get enough new fluid to matter. As many people know, retracting rear pistons is a pain. Doing it more then really needed could damage the seals. I wouldn’t do it this way.
To keep fluid from running out of the MC while you drain the rear calipers,
drop a patch of rubber or soft plastic into the bottom of the MC tank. Set a
CLEAN weight on it if need be. (Clean the stuff with brake parts cleaner! This will help anytime you need to open/remove a caliper and don’t want the MC to
go dry.) Use a small enough weight that you can put the cover back on the MC while you mess with the calipers.
Here are a few ideas I’ve been playing with. (I’m not in a big hurry to mess with these…)
You can try dismounting the caliper, removing the bleeders and draining them. Wiggling the E brake arm might help get them started draining.
If it won’t drain, you could try to use a syringe to push air into the bleeder hole. The trick would be to find a tube thin enough to fit through the bleeder hole and not block it completely. The tube has to reach all the way inside the caliper so air will go in and allow the fluid out.
It may also be possible to suck out the fluid through the bleeder using a syringe or a vacuum bleeder set. Don’t try to reach all the way to the bottom or you’ll suck in stuff that will probably block the tube. If this works, it would save having to take the caliper off the bracket.
What makes the rears even more difficult is that many of them have bleeder repair sets installed. The repair sets usually have smaller openings than normal ones. In this case, you may never get them flushed without disassembling them.

I found this in a pdf file from I don’t know where. But seems to be a good write up on how to do a brake mod. It also clears up an issue I saw on another sire about what other master brake cylinders you can use. The best part about this there is a Bill of Materials at the end for you to use.

Walt Zettner’s Brake Upgrade

Originally published in the Pontiac Connection magazine, 4Q97 issue. Reprinted by permission from the author.

Scans of the three required brackets are at the bottom of the article. If, when viewing them in your browser, the top edge is cut off, save them to your PC by right clicking on the link and selecting “save link as..” or by using “save as” while viewing the image in your browser. Then open the file in a local image viewer. The complete scan is in the file, also there are .dfx & pdf file to download as well.

Whoa! or… Stop That Fiero

By Watt Zettner

Tim “The Tool Ma” Taylor and I have a lot in common. More, bigger, faster… it is really easy for me to identify with him. Since 1987, I have dreamed of building a V8 Fiero. Last August, a silver metallic 1987 SE Coupe spoke to me. Very clearly, the Fiero told me that this was my chance and it may never come again. I bought the Fiero and over an enjoyable six month period I engineered and installed a 350 small block Chevy with estimated 448 bhp. Uaargh! Uaargh!

Being the sensible person that I am, I rebuild the brakes by turning the rotors and installing new premium pads. The stock brakes are OK, but they were not bigger or better than any other Fiero. Uarrgh! Uarrgh!

So I set out, to develop some big, efficient brakes. My goal was not to avoid paying the price for purchasing a brake kit, but to derive enjoyment from using my engineering and shop skills to upgrade the brakes to be ona par with the engine conversion.

The following brake conversion uses mostly off-the-shelf parts and few simple fabrications. I had in mind using the largest disc I could fit under my street wheels, which are Chevrolet Beretta GTU 16″ x 7″ aluminum. This conversion was done to a 1987 Fiero and all should apply to 1984 through 1987 Fiero’s, all models. I do not know the compatibility with the changes of the 1988 model year.

In beginning my research for the project, I gathered some initial information from the internet, including the Fiero List Archives and several very helpful home pages. Most valuable was a Hot Rod magazine on the Fiero Indy Pace Car published in 1984. It gave some strong hints for a starting point on the calipers. Continuing my research, I made friends with the neighborhood Car Quest Auto Parts Store. Telling them about my plan, they became very interested, and provided help the average walk-up customer may not get. I will go into this briefly, because the procedure is universal in projects of this type.

From a high shelf, they produced the Car Quest “Brake Illustration Guide.” The book is a wealth of information. The illustrations are clear photographs, in two views, of literally hundreds of brake calipers, showing all of their basic features. Likewise, there are dimensioned, two-view, drawings of all the commonly used brake discs. Master cylinders are shown in photos like the calipers, with bore sizes listed.

This book is fully ¾ inch thick with much more information that I reference here. They also loaned me a Car Quest “Brake Buyer’s Guild” which ties the illustrations to their years, make, and models. The book I used were current through 1994. Therefore, this is the latest year referenced in the bill of materials. Many of the same parts carry forward 10 1996 and 1997.

The search started by scanning the list of dimensions for the rotor disks. I highlighted some twenty or so models that had the 100 mm = 5 Fiero lug hole pattern. I chose only the vented disks from that group. I settled on a disk number 5353. A check in the Buyer’s Guild, showed this rotor is the rear of the 1989-1994 Chrysler LeBaron and several other Chrysler products. It is 11.260″ diameter, vented, with the 100 mm x 5 lug pattern.

A similar search turned up suitable front and rear calipers. The front were a no-brainer. 1989-1992 Camaro calipers fit the bill. The rears were a little more difficult. I wanted the front and rear pads to be identical. Having narrowed the choice, I prevailed on the Car Quest owner to arrange for me to visit the distribution center where I could look at three calipers. The features I could not discern from the photos became clear on first hand examination.

The trick was finding a rear caliper to function with the stock Fiero parking cable arrangement. Some people mistakenly rationalize that they never use the hand brake, therefore they won’t miss it. Definitely you should retain the emergency brake function.

The rear Camaro units that correspond with the front do not work because one cable would pull forward and the other aft. The Fiero requires that both pull to the rear. 1980-1985 Cadillac Seville calipers met the requirements. Be careful that the calipers you get are marked with casting number 020 and the other with 021. They are mirror images of each other in that one is a right and the other a left. In out application, the sides are reversed. We will re-use the parking brake levers and return springs form the Fiero calipers. No modifications are required!

The master cylinder selected is for late model Chevrolet C/K pickups a Blazers. It is made by Bendix and is of the same family of master cylinders as the stock Fiero unit. To look at the two, they are identical, varying only in the bore size. Our choice is 1-1/8″ bore to pump more fluid to the larger caliper bores, thus maintaining a pedal stroke equal to the original. Installation is a perfect bolt in replacement.

Using a PC CAD program, designing the caliper brackets was simple. Two designs sufficed, one for the front pair and one for the rear pair. The accompanying drawings show the simplicity. The dimensions are accurate for 11.260 inch rotors. Should you choose smaller rotors, you must make an adjustment equal to the difference in the rotor radii. Thus 10.5 inch rotor would require the caliper to be mounted (11.260-10.5)/2=0.380 inches closer to the hub center. The X coordinate distance between the drilled holes and the tapped holes would be reduced by 0.380 inches.

The caliper brackets are flame cut from 3/8 inch mild steel plate. Machining consisted of drilling four holes and tapping two of them, and milling or grinding the 1/8 inch machining allowance from thrust surfaces for the calipers.

The front require spacers 1.00 OD x .50 ID x .435 inches thick to align the calipers with the rotor. The rears require a similar space, but only 060″ thick. Use a flat washer. The test is to be able to freely turn the rotor with the calipers installed. Misalignment will cause the pads to drag. Your actual spacer thickness may very, but if by more than a few thousandths, look for something bent or deformed.

At the rear, two “boomerang” shaped brackets are fashioned from ¼ inch mild steel plate to anchor the parking (emergency) brake cable to the calipers. The two larger bolt holes in the bracket are secured under the nuts on the forward side of the 16 mm strut-to-knuckle mounting bolts. The original washers go under the fabricated bracket. Be cautioned that if you move the strut in relation to the rear hub carrier while the bolts are loosened, you are asking for a rear wheel alignment. If your car’s handling becomes strange, or your steering wheel is not centered after installation, then one or both of them moved. Carefully mark the relationship of the parts so that they may be restored to the original location.

The Fiero front rotors must be modified. Take them to a machine shop and have the rotor disk portion “parted-off” in a lathe, leaving the edge of the hub flange about 5/8 inches thick. This gives you a beautiful little hub with no brake disk. The studs are then knockout and replaced with longer, 55 mm studs. The extra length is needed for the added thickness of the LeBaron brake disk, which is installed over the studs.

While you are at the machine shop, have them put one pass of machine able cast iron weld in the bore (center hole) of your front disks and bore to fit the hubs. You will have reduced the diameter by 0.018 inches. Conversely, the rear rotors need the bore enlarged 0.018 inches to fit the rear hubs.

The tapped caliper bolt holes in the Fiero knuckles and front spindles must be drilled out to 27/64 inches and tapped with a 12M1.50 metric tap. If you are not compulsive, you are free to drill and tap a 7/16 inch English thread. Adjust the tap drill size accordingly. The balance of the job is bolt together and plumbing. The stock rubber hoses are not suitable for a high performance brake system and they are too short. Use the stainless braided hoses referenced in the Bill of Materials.

Caution: During disassembly and re-assemble, refer to appropriate sections of your Fiero shop manual. If you are not a “brake” person, get help from someone who is. The lives of you and your loved ones depend on the quality of the work you do during this project. Always use jack stands and an adequate floor jack when raising the car. The Fiero jack is for on-the-road emergency situations only.
Check for fit and alignment on each step of the assembly process. Check for clearance of the brake hoses. Use rubber insulated straps to secure them out of harm’s way. Turn the steering, full lock to lock, watch for clearance, and beware of “banjo-string” tension on the hoses. Likewise, check for free rotation as you assemble each part, including mounting the wheels. It is embarrassing to finish up the job only to find that your wheels won’t turn. I had some minor interference between the inside of my aluminum wheels and the rear calipers, which was corrected by light grinding of the caliper casting.

There is no alternative to a perfect brake bleeding job for good brakes. I recommend a small hand-operated vacuum pump that is sold in the Wal-Mart automotive department for a bout $20. Start with the right rear caliper(farthest from the master cylinder) and work to the caliper closest to the master cylinder. I suggest draining all the old fluid and using all new DOT 3 or better brake fluid. Do not re-use the bled fluid.

Perform the obvious driveway slow speed brake check first. Do several miles of start and stop driving to allow out pads to seat in before you try your 60 mph to zero test stops. I retained the standard Fiero proportioning valve and performance is perfect, with no premature locking up, front or rear.

There are several ways of doing this modification and this is but one. The cost was approximately $600 in parts for all four corners and master cylinder. My results are pleasing. The brakes provide a great match for the 448 bhp engine in autocross competition. I hope to be able to provide actual stopping distances in the future communication. In the meantime, I will be glade to provide additional details on this brake modification to anyone interested vai email. Imay be reached at waltz@satx.rr.com (email address updated 2/27/2001 – dwc).

Next comes a power steering project for my car.

SOURCES AND REFERENCES:

All of the rotors, calipers, master cylinder in the Bill of Materials following are manufactured or rebuilt by Car Quest and are available at any Car Quest store. My favorite Car Quest dealer is Mission Auto Parts, 2918 Roosevelt Ave., San Antonio, Texas, 78214, (210) 921-2803. They have a copy of the Bill of Materials for reference. Hint: Shop around for at least a 20% discount for your parts. Work the best deal you can on the cores and/or core charges when buying rebuilt. The core charges for the rear calipers are significant.

BILL OF MATERIALS

See the parts list below.

BRAKE MODIFICATION NOTES

It is possible to reuse the front hoses on the rear (in a pinch), but longer hoses are need on the front. 1988 front hoses are 2″ longer and should work in the front. The braided hoses are probably less expensive.

Wheels: sixteen-inch wheels are required to clear the calipers in stalled over 11.25″ discs. Smaller diameter disks are available at 10.5″ for possible clearance with fifteen-inch wheels. I did not research this.

If smaller rotors are used, the drawings for caliper adapters must be altered, i.e., holes will be moved .5 x (reduction in diameter) toward the center of the hub. (See text.)

Rear calipers are installed reversed from the original Cadillac Seville application to allow the hand brake cables to pull to the rear.

Stock Fiero hand brake cables and return springs are used.

A 1.125″ master cylinder is not mandatory, but is recommended to avoid approximately 1″ added pedal travel that will result from using the stock master cylinder with the new, lager caliper cylinder sizes.

Bill of Materials:

4 each Raybestos P/N 7993 11.260″ Vented Rotors (rear, 89-94 Chrysler LeBaron)
1 each CarQuest P/N 18-4071 Front Caliper, rebuilt, 82-92 Chevrolet Camaro (note 1)
1 each CarQuest P/N 18-4072 Front Caliper, rebuilt, 82-92 Chevrolet Camaro (note 1)
1 each CarQuest P/N 18-4138 Rear Caliper, rebuilt, 80-85 Cadillac
1 each CarQuest P/N 18-4139 Rear Caliper, rebuilt, 80-85 Cadillac
(These calipers must be identified with casting Nos. 020 and 021)
8 each Caliper bolts
2 sets CarQuest P/N D-154 Disc Pads (Front and rear are same)
1 each CarQuest P/N 2218 Master Cylinder, (92-94 Chev/GMC Blazer/Jimmy) Aluminum, 1.125″ bore
4 each 3/16″ X 24″ Teflon stainless steel braided brake hoses. (Stock hoses are too short)
4 each Earls P/N 600773 .400″ Banjo fittings for above
4 each Earls P/N 989534 Female 10mm X 1 adapter ends for above
4 each 1/4″ AN-type rubber insulated clamps (to secure brake hoses)
10 each Dorman P/N 610-323 Wheel studs, 12M1.50, X 55mm X 12.67mm knurl diameter wheel studs for front hubs.
2 each Caliper adapters for front, (burned, drilled and tapped 3/8″ steel plate)
2 each Caliper adapters for rear, (burned, drilled and tapped 3/8″ steel plate)
4 each 12M1.50 X 40mm Hex head cap screws for front adapters.
8 each 12mm or 1/2″ Split Lock washers for 12 mm bolts
4 each 12M1.50 X 25mm Hex head cap screws for rear adapters.
4 each 1″ Round X .500″ X .435″ thick spacers for front caliper adapters.
4 each .060″ thick SAE flat washers for rear caliper spacers.
2 each E-brake cable housing stops (burned and drilled 1/4″ plate)
1 quart SAE 3 or better Brake Fluid
1 each 12M1.50 Starting tap
1 each 27/64 High Speed Twist Drill

Re-used Materials

4 each Banjo fitting bolts from Fiero calipers
2 each Front hub assemblies, modified with the disc rotors machined off to leave hub flange approximately 5/8″ thick.
2 each Fiero E-brake cable return springs.
1 lot Fiero E-brake cables.

These are the images that were in the PDF file.

Here are some othere images and drawings from .dfx, .ems, .pdf, .xps and .tif files

front_caliper_brackets.DXF (165)	rear_caliper_brackets1.DXF (114)	rear_caliper_brackets3.DXF (96)
front_caliper_brackets.ems (90)	rear_caliper_brackets1.ems (56)	rear_caliper_brackets3.ems (72)
front_caliper_brackets.pdf (169)	rear_caliper_brackets1.pdf (128)	rear_caliper_brackets3.pdf (109)
front_caliper_brackets.xps (93)	rear_caliper_brackets1.xps (58)	rear_caliper_brackets3.xps (63)
front_caliper_brackets.tif (113)	rear_caliper_brackets1.tif (88)	rear_caliper_brackets3.tif (86)
The .ems files are for use with “eMachineShop” you can also place orders for the brackets with this application as well. But it seems very expensive. Example the front caliper bracket their price $251.87 for one you need two. You can build them using 3/8” mild steel plate.

Adjustment

There are several adjustments that affect window position and function. When making adjustments go in small increments or you can damage the window machinery or the door seal. The adjustments are the same for both power and hand operated windows.
Warning! If you move a door from one car to another then these adjustments MUST be checked carefully. Failure to get them right will result in wind noise, water leaks, damage to the door seal or window hardware, window breakage, or all the above.
Note: Oops, This page isn’t quite finished. I have to add the picture as soon as I get the film processed. Sorry. (Easier to leave it here now than edit links…..)

Upper stops

There are 2 stops that set the upper limit of travel. (You can’t adjust the bottom.) They are near the front and rear top corners of the door. Use these adjusters if the window is too far or not far enough up to seal at the top. You can adjust the front and rear stop independently but keep in mind that adjusting one may affect the other. (Blue dots in Picture 1)

For/aft position

There is a single wheel riding in a vertical track near the rear of the door. The track is adjusted by loosening the nuts one the top and bottom of the track.
(The bottom must be loose or the top won’t move.) This track will move the window front to rear. Adjust this track if the window edge doesn’t align with the vertical sections of the door seal. If this track is to far forward the window will bind in the front part of the door seal and damage it. (Red dots in Picture 1)

Pinch

There are two pinch guides. These are on the top of the door. Adjust them with the window down. Pinch the window only tight enough to keep it in place. Over tightening these is part of why the windows get scratched by the outside pinch guides on the Dew Wipe. (Green dots in Picture 1)

Nose track

The nose track should almost never need adjustment. However if you are removing the door you’ll find it much easier to remove the nose track first.
(You must move this track to get to the hinges from the interior side of the door!) This track is held to the door framing by 2 bolts. With the window up,
and the outer skin off, it will drop out the bottom of the door once the bolts are removed. Note that these 2 bolts are not the adjustment for the nose track. The adjustment is on the upper bracket inside the door. (The bolts to remove the nose track are the Yellow dots in Picture 1.)

Hardware Cleaning & Lubrication

First off, don’t spray anything on the nose or tail tracks that the glass rides in.
All you’ll do is make a hell of a mess and you could even damage the track lining. If the tracks are crudded up then tack them out and wash them. Unless the tracks are out of adjustment, rare but can happen, they are unlikely to be any problem.
For the rest of the tracks you’ll need some “white” grease and some oil. For the oil, I like Valvoline’s SynPower Penetrating Spray Lubricant or Pyroil White Lithium Grease. I’ve also used CRC 556 with good results. These products penetrate but they carry more lubricant than products like WD 40 or Liquid Wrench. WD-40 tends to evaporate and Liquid Wrench actually stiffens when cold. (Liquid Wrench can freeze. Never use it in outdoor locks.)
What is White Grease and why use it? White Grease is very light Lithium based grease. It doesn’t stink like many other types of grease do when they get warm. When you’re doing work like the window tracks you want light grease that won’t stiffen much in cold weather and White grease fits that bill very well. From past use, White grease appears less hostile to plastics than most regular grease. I usually buy it in the over sized “tooth paste tube” style package.
The big problem with window lubrication is the rollers. They are usually worn out and don’t want to roll even with lubrication. With the tracks well greased they will at least slide more easily. I think the rollers can be replaced but you’ll have to rip the entire door apart. I have no idea if or where you can get new ones. You may be able to get decent ones of another GM car. Try getting them from the passenger’s door since that usually gets less use, especially in cars w/o power windows. They look like they are just snapped onto the pivots but I’ve never had the occasion to test that theory on Fiero.

The Rollers

The roller pivot gets a good shot with the spray lubricant. If the rollers are in half decent shape this should wash the crud out of them. If you extend the spray straw you can then bend it around to get the hard to reach ones.

The Tracks

The Vertical track runs up the door behind where the armrest goes. It’s this track that does most of the work of guiding the window. The window has two wheels in that ride in it.
The Lift Track attached to the glass and it responsible for the actual up and down motion. There are two rollers running in this track, the front one will be a pain to get at.

1. Lower the window and put some white grease into the track just above the rollers.
2. Raise the window to the top and put some grease below the rollers.
3. Run the window a couple times to spread the grease, add more as needed.

The Regulator

I use a screwdriver to spread the coils of the counter balance spring and then drench it with spray oil to wash out the crud. After that I blot up as much of the oil and dirt as I can then work in some white grease.
I give the pivot and crank shaft bearings a good shot of the spray oil and I put some grease on the gear teeth. I usually use something heavier to grease the gear teeth.

Power Motors

I find these motors rarely need internal work but in case you want to grease inside these, make sure you don’t get any lubricant on the brushes or armature. Lube on there will usually kill the motor in short order.
The gears inside the motor need regular grease. The worm gear in there generates quite allot of friction and pressure. Any good Molly or Synthetic grease works well.

Fiero Tips and Tricks

Sail Panels Have you ever wondered how that sail panel is held  to the body? The picture here to the right show an  85 SE with the panel removed. I recommend you  remove it if you are going to paint your car or if you  need to repaint the panel.	REMOVING THE NUT TO RELEASE THE FORWARD CLIP
Please note that if you only want to replace the  plastic sail panel, it can without removing it from the  car. Removed the plastic panel by working putty  knife at each corner carefully. It will start to lift and  crack, and break off. Just work carefully. Once the  quarter panel is removed, use 3M General Purpose  Adhesive Cleaner (PN 051135-08984) to remove  the old double-sided tape. Clean the panel well and  then replace the tape (3M PN 05131-06384) and  install the new plastic sail panel.	85 FIERO WITH SAIL PANEL REMOVED
Removing the Sail Panel Remove the seats from the car. Remove the seat belt bolts and the upper rear trim piece. Look through the lower hole and remove the nut. Lift the front of the sail panel about a quarter to one half inch. Find the two tabs protruding into the body skin. I have found two types of fasteners that hold the rear of the panel in place. The first type has a lever. Work these loose, you may try a scribe with a right angle to get behind the tab and pull back a little to release. The second type has a threaded stud that pushes through a metal clip on the body. Lift the sail panel off.	TAB PIECE THAT HOLDS REAR OF SAIL PANEL (TYPE 1)
Installing the Sail Panel Install all the clips on the Sail Panel and align the Sail Panel with the rear holes and the front hole and push it in place. Reinstall the nut on the front stud.	METAL CLIP ON 85 FIERO
	THREADED STUD THAT PUSHES THROUGH THE METAL CLIP

The 1987 Sport Coupe uses a polypropylene skirt under the front of the car.

(I’m guessing at the specific plastic from the way it feels, and it’s response to abrasion, and heat. At any rate it is a Thermo Forming plastic. I imagine it could be LDPE as well. [Low Density PolyEthylene.])
Two things happen to the skirt. It gets torn, or it deforms. A torn skirt is difficult to repair. I’ve yet to find an adhesive that is flexible enough to work on a polypropylene for any length of time. They are all either to stiff and crack apart with a good whack, or they just don’t stick in the first place. My feeling is that only thermal, or ultrasonic, welding will hold a tear together like it wasn’t there. (Solvent welding doesn’t seem to work either.)

A deformed skirt on the other hand can be reworked with the CAREFULL application of heat. The trick it to heat an area without blistering, or melting it.

WARNING: Thermo Form plastics like polypropylene, and polyethylene can hold a tremendous amount of heat for a long time! DO NOT touch the area you where heating without good gloves! Do Not touch the front of the work or you may leave irreversible marks on it.

You MUST support the ENTIRE skirt while working on it. If you don’t you could end up with a sudden collapse that will ruin the skirt completely.

You want to heat the area you need to form evenly, and most of the time from the BACK side of the work. (If you heat the front you’ll make scuffs look worse.

Direct heat will open any scratches.) You can use a heat gun, or a propane torch with a big tip, and preferably a flame spreader. Work carefully and keep the heat source in constant motion. If you use a torch use a very low setting.

DO NOT use MAPP, Oxy/MAPP, Oxy/Propane, or any other metal welding/cutting torch.

Try practicing on the lids of some takeout soup containers. They have very close to the same properties as the skirt, even if they are thinner. (soup lids are LDPE, the containers are HDPE.)

Fiero Hood System
Few people realize that the hood of any car or light truck is actually a somewhat complicated system with several safety features most people don’t even notice. The only feature many people are aware of is the secondary latch on hoods that open from the front. (That second latch is actually required under FMVSS 571.113.) Fiero doesn’t need that since the hood opens from the back.

Hood Alignment

If you are having trouble aligning your hood, check for bent hinges. The hinges are fairly easy to bend and just a small bend can keep you from getting the hood straight.

Broken release or jammed latch

The first couple work for allot of cars with cable release. To release a stuck latch, try pushing down on the hood or banging over the latch with your hand while someone else pulls the cable. Once you get it open don’t forget to clean and lube the latch. Silicone greases seem to work best. If the cable or handle breaks… There is a second release cable hidden in the release lever assembly under the dash. Unscrew the lever from the dash to access this cable.
If you’ve broken both cables or the latch is too badly jammed, Skitime made a neat little tool for dealing with the latch without damaging your car. You can read about that here.

Anti Guillotine

Fiero hoods have a secondary locking system designed to keep the hood from coming thru the windscreen during a wreck. The system is comprised of two bolts, one at each rear corner of the hood, which fit into keyhole openings in the hood. When the hood is shoved back, these bolts lock in the keyholes providing much more anchorage, taking more load than the main latch could ever hope to hold.
The Anti Guillotine system also includes a break line across the hood framing that is intended to allow the hood to fold up in a controlled manor. In Fiero you’ll see four clearly visible notches across the hood frame starting next to the support bracket. (In a crash… Fiber glass hoods will usually break wherever they want. The break line does more for metal hoods most of the time.)
While this system is a really good thing in a big wreck, many Fiero owners have found it quite annoying after a small bump. If the hood is shoved back only a little, you may be able to unbolt the hinges and slide it forward to get it off the bolts. (Sometimes you can just grab the hood and pull forward.) If on the other hand the bolts have locked in the hood you will have to drill the hood to access the bolt heads.
If you have a hood you are trying to save, and assuming that the slots in the hood have not been torn by the bolts, they should end up in about the spot shown below. You’ll need to try one of two things to get them loose.

Note: If the slots have torn, the hood should be discarded even if it looks ok otherwise. Torn slots will likely fail completely in another impact and allow the hood to come thru the glass.
Drill a 3/8″ hole in the area shown so you can insert a Torx® bit to unscrew the bolts. Once the bolts are loose, open the hood and use a piece of metal to spread the tabs. I haven’t tried this but if it works it leaves you with a minimal hole to repair in the hood.
Open a larger hole at the point shown so you can unscrew the bolt and pull it out.
The dimensions shown are as close as I could measure them to the center of where the bolt should end up. I measured from the bottom using a good hood. As I mentioned, if the holes have torn at all you should scrap the hood for safety even if the thing looks good in all other ways.

Do Anti Guillotine systems exist on other vehicles?

Yes. There are several ways it is done depending on make and model. In some cases you may see what looks like a hook sticking off the hood of front or rear opening hoods. Most front opening hoods just use the hinges. You’ll usually see the break line across the middle of most hoods but they may not be as obvious as the one across the Fiero hood.
Because of Anti Guillotine features, there is a big problem with many modifications to hoods. If a modification makes the hood stiffer, it may fail to break/fold in a wreck and come thru the glass. Even with strong hinges or supplemental anchors like Fiero uses, the hood may just tear away and move straight back. Fortunately many modifications use fiberglass or plastic parts that are not very strong but this is still an issue to watch for when doing custom work.

As many people know, the exterior dew wiper has 2 fuzzy pads on it. These pads collect trash or wear out and damage the window.
I’ve had the doors apart a bunch recently and I’ve noticed the pads are very tight to the glass. This adds to the problem. The pads are pressing so hard they wear off the fuzz. They also trap small particles that scratch the glass.
The exterior fuzzy pads have an interior counter part. The interior pads can be adjusted. When you replace the exterior wipes adjust the interior pads so they are guiding the glass without pinching so hard the pads cause damage.
You need to remove the interior door skin to access the pad retaining bolts.
There is one 10mm retaining bolt for each of the 2 pads. The bolts are on the top of the door framing. Loosen these pads before installing the new exterior wipes. This also gives more room to remove the exterior wipe’s screws.
When you tighten the bolts push the pads up only enough to guide the glass and keep it from rattling. Don’t push them so tight they are clamping. This will allow fine particles to work past the exterior pad instead of being trapped between the glass and the pad’s metal guts. It will also avoid excess wear on the pads.

Those of you who have wipes that are in reasonable shape can keep them from collecting stuff the same way. Just move the inner pads away from the glass, clean the exterior pads, then push the pads up just snug to the glass and tighten the bolts. Don’t lean on them like Pontiac did at the factory.
In fact if the pads aren’t completely shot but the wipe is, cleaning and backing off the pads will help to prevent further scratching until you can replace the wipes. When you do this try to knock loose the dirt in the pads by gently running something dull, or maybe an old toothbrush over the pad front to back.
I did this on one of my crummy wipes and it’s helped quite a bit. I no longer hear it grinding as it goes down.

WARNING: Doors are Heavy! You will need helper(s) to remove/install doors or rebuild the hinges. If you must work by yourself you can use a floor jack with wood or other padding on top to support the door. Don’t use a “bottle” jack. They are too easy to knock over.

Here’s a guide on how to work on each area of the Fiero’s unique door assembly. The MotorMite products below should come in handy and will save you fooling with a GM dealer.

Hinge Service.

WARNING: The spring in the bottom door hinge is under heavy load at all times. Use extreme caution working in the hinges.
Note: To remove/adjust the door side of the hinges without removing the outer skin, you need to remove the bolts from the front window track and drop the track into the bottom of the door. (Two bolts hold the track and the window must be up.) You’ll also need a ratchet handle, long extension,
and a flex joint to go with the correct socket.
Note: Yes, if the pins and locking clips are ok, you can replace just the bushings. You have to remove the locking clip from the pin carefully but it is reusable. (Gently spread the seam of the clip until it will slide along the pin.)
Let’s face it sooner or later you will need new hinge pins for your doors. The problem with the OEM bushings is they don’t provide much bearing surface between the hinge sections. The bushings are made for rotational loading not the heavy axial load they get as well. (Axial load is the vertical load along the pin centers.) This problem results in the hinge wearing a depression where the bearing flange rubs and/or the flange crumbles. This allows the 2 halves of the hinge to rub and bind. Even new brass will quickly wear off the flanges on the top bushings. To eliminate the problem permanently there is a small change you can make to the bottom hinge that will make the door work like new for many years.
After you replace the bushings insert a nylon washer into the bottom hinge as shown in the drawing below before inserting the pin. The washer will take the weight off the flanges of the top bushings in both hinges and increase bearing surface tremendously. The washer will put the hinge in proper alignment and keep it there for years.
The nylon or copper washers used for sealing the oil drain plugs are perfect for this use. They fit like they were made for it. You can get them at most parts stores. I prefer nylon myself. It’s more slick than copper.
Lube the bushings and washer with brake grease or some other grease that won’t easily wash out.
You may have to adjust the bottom hinge just a smidgen depending on the thickness of the washer you use. The adjustment is inside the door. (The post side is not adjustable.) In most cases no adjustment should be needed.
Why not put washers in the top and bottom hinges? There is not enough metal in the top to do this. It’s not needed anyway. With this change the bottom hinge will take all the axial loads and is more than strong enough to do so. Leave the top hinge so the 2 halves are not rubbing at all.

Hinge Spring Tool

Here’s a note from Carrolles that was posted in the thread “Popping off the doors?? Help a brother out!!” This tool is worth having even if you only use it one time. You may also be able to borrow one from some parts stores. Many of the chain stores have loaner tools.
I got the Steck GM Door Hinge Spring Tool from Tools USA (800) 451-2425
look under hand/specialty tools or go directly to the page via the following link:
Hand & Specialty Tools, page 4 of 6
Part number (they call it ID number) 4520
Current cost is $15.25 us
Take care,
Carroll
(Quote links edited for clarity. Cost is correct as of 28-Aug-01.)

The interior door skin

Removal of the interior skin is simplified by purchasing 2 tools, a panel lifter and a window crank tool if you have manual windows.
The armrest is held by three #3 Phillips screws. One is under the decorative plug at the top of the handle section.
A hidden clip holds the window crank. Line the tool up with the crank knob and slide between the handle and wear guard disk to push out the clip. The slot in the handle can be tight. Wiggle the tool until it drops in the slot. Note: If the handle was previously removed the clip may be on backward. (To reinstall the handle put the clip in the slot with the open side toward the knob then just push it onto the shaft.)
The door handle trim is held by two #2 Phillips screws. One is under the logo and the other is under a tin cap. Once the screws are out carefully remove the lock button from the lock rod. The lock button pulls of toward you and it’s held rather tight. Rotate the trim plate as you lift it around the handle.
1 set screw on the window side of the trim holds the driver’s side mirror control in it’s place.
Work your way around the panel with the panel lifter and carefully pry out the clips. Avoid damaging the panel. Clips are fairly easy to replace but panel damage can be hard to fix.
Note! There is usually a fastener on the rear bottom corner of the door panel that is cut short. This is done so that the window will not hit it. If you replace this fastener and don’t trim it by about 1/3 then it will snag the window near the bottom of its travel.

Mirror

Two 10mm nuts hold the mirror. The nuts are accessed by removing the rubber filler in front of the window opening. There are three #2 Phillips screws holding the filler, one of them is normally hidden under the inner skin.

Power Mirrors

There is an electrical connection inside the door. Carefully fish it out of the hole and disconnect it.

Inner Dew seal

Four #2 Phillips screws and a metal strip hold inner Dew Seal. It rests on top of the door edge.

Outer Dew seal

The outer Dew Seal is held by the mirror nuts and some #2 Phillips screws. To gain clearance for access to the screws, remove the inner seal and release the inner pressure guides on the top of the door. There are 2 guides held by a single stud in each. Rodney Dickman sells a tool to make removing these screws easier. You can make one fairly easy by epoxying a #2 Phillips screw bit to any length of stiff metal. Just be careful not to scratch the glass. (Rodney’s tool is coated to help prevent scratching.)

The exterior door skin

Removal of the exterior skin requires removal of the interior skin and the mirror. The door skins are attached by the following hardware:

• 2 7mm hex head sheet metal screws (hidden under exterior trim)
• T30 Torx head machine screws
• 4 plastic rivets
• 1 rod clip on the door handle
• 1 “christmas tree” fastener

The removing the door skins requires removing the interior trim and panel. This in itself is annoying. You will want to take the clip off the window handle. You may need to run the window up and down at times while you work. (Always roll down the window when the door is off the car!)
The trim across the middle of the skin releases by carefully prying out the Christmas tree under the outside door handle. The rest of the clips are released from behind the skin. The front most clip must be carefully pulled out of the trim as it’s screwed down. (You do not have to remove the small piece of trim aft of the handle.)
Leave the door handle and lock rod alone until the skin is loose. The door handle link will slide out of the latch as you lift the skin off. There is only one place in the latch where the link will fit to reassemble the skin. Dropping the rod into the latch is a little tricky but is much easier than messing with the handle clip from inside the door. You also don’t get cut up this way.
The lock linkage is very easy to get off and on with the panel loose. (Handle
the panel carefully until you free the lock clip.) To remove the lock linkage, carefully pry up the top of the clip and push it down the arm away from the lock. To install the lock linkage, put the clip on the lock arm first then press the linkage into the arm until it clicks into place. Remove the mirror.
Remove the 2 hex head sheet metal screws that are under the trim. (7mm heads)
Carefully break or drill out the 4 plastic pop rivets on the bottom of the door.
Be careful not to crack the skin.
Remove the T30 Torx screws from the front and back edges of the skin. Make sure you place the bit fully into the screws and hold it straight or you will strip out the screws.
Pull the panel out at the bottom. Lift the panel off the hooks at the top. Be careful not to break the tabs on top of the skin.
When you reassemble the door you have to come up with something to replace the broken rivets, and hold the trim if you broke the clips.
Blobs of silicon inside the door can hold the trim on what is left of the clips.
Usually the ear beaks out of the clip leaving a nice loop. Some little wood or plastic wedges in the loops will hold the thing tight while the silicon sets.
The door rivets can be replaced with either christmas trees, or plastic screw rivets. Suitable screw rivets are Rivet-Tite #47954. These are 1/4-inch diameter and fit like they where original. They are also reentrant should you need to do this again. You need 2 packages per door and the total cost per door is about $3. (christmas trees are also reentrant, but repeated prying risks cracking the door skin.) I don’t recommend use of metallic fasteners.

Skin Adjustment

(Calling the dermatologist…)
The exterior skin on Fiero doors is adjustable but, like practically everything else on the car, there is a trick to it.

A bit of background

When Fiero was assembled, Pontiac needed a way to allow the door skin to be adjusted to clear the fender etc. The problem is that the skin had to be locked in place after adjustment. This was accomplished with a single screw in the door skin.
Inside the door by the exterior lock, there is an adjustable plastic slug. Once the skin position was adjusted, Pontiac drove a screw into this slug to lock the location. This single screw is one of the major factors that has confused many people into thinking the doors are custom to each car.

Adjustment

Note: Adjusting the door skin may expose areas scuffed by the mirror
gasket. You may or may not be able to cover this by adjusting the mirror.

Loosen the screws along the front and back of the door skin.
Remove the molding between the door handle and front of the door.
There are 2 screws under the molding. Loosen the front one. Remove the one by the door handle.
You don’t have to worry about the mirror or bottom rivets. The mirror isn’t attached to the skin. The rivets are in slots.
The skin is now free for adjustment. There’s about 1/4 to 3/8 inch of play front to back.
Once the new position is determined, lock the skin by driving in the screw by the door handle. Note that if you are close to the old hole in the slug, (and I expect you will be) you can either stuff it or rotate the slug slightly. If you stuff it, glue the stuffing in place.
Tighten all the other fasteners, replace the molding and you’re finished.

Since I had to replace the other one recently, I figured it was time to revisit this article.
The Constant Velocity shafts in Fiero aren’t very difficult to work on but it certainly helps to know a few tricks.

Axle Nut

WARNING: The axle nut will need to be turned with a wrench for all but the tip of the axle shaft and can get quite hot while spinning. Be careful handling the nut and the socket. The nut can burn you. The socket may get uncomfortably warm.
The 30mm locknut used on Fiero drive axles is intended to be a single use item. It should be replaced each time it’s removed. The nut isn’t likely to fall off. The axle can’t come out even if it did, but if the nut comes loose you can out wear the hub and axle splines in no time. At that point you’ll need a new hub and axle… (An axle with spline damage may not be accepted for core… That could cost you from $20-50 above the normal cost of the axle.) I strongly recommend a new nut any time the thing is off. It’s cheap insurance. ($3.00-$5.00) The nut is available at most parts stores. I won’t reuse one more than a couple times. This nut wears considerably when you work with it and the heat of remove/replace messes with the hardness of the nut. If you get a single click noise as you brake or accelerate then this nut may not be tight enough.

(Torque spec source: Axle, Haynes Fiero repair book 79008. Lugs, Raybestos.)
Note: A note in the forums indicates the correct torque is actually 170 ft-lbs for a used nut. This makes more sense. It’s been my experience that a used nut will need more than 70ft-lbs torque or the axle will do the single click thing. To reach 200ft-lbs you’ll need to be very strong or use about 3 feet of handle on the socket.
You really want the wheel on to remove and replace the nut. The suspension bounce can make it very difficult to tighten the nut. You could even knock the car off the jacks trying to do it with the wheel off. You’ll get the best results if the car is on the ground with someone holding the brakes while you tighten the nut. Use the spare tire if Aluminum wheels don’t have enough room to let the socket in.

Axle Removal

Trick One

There are a few ways to get the axle out. I prefer this one.
· Unfasten the brake line from the strut.
· Unfasten the brake caliper from its mount and tie it up so it’s not dangling from the cable or hose.
· Remove the pinch bolt from the ball joint.
· Separate the ball joint.
The whole assembly can now be swung out to clear the end of the axle without messing with the tie rod.
If you push in on the axle, you’ll compress the inner CV and gain additional clearance.
Some people prefer to reverse this a bit. They leave the brake caliper attached and separate the tie rod. If you do this be very careful you don’t damage the hand brake cable or the brake hose.

Trick Two

Note… The axle often lets go easier if you can give the thing a quick pop instead of just prying on it.
A clip inside the transmission holds the axle. This can make extracting the axle a pain.
With stubborn axles, it may easier to pop the axle if you use 2 pry bars. Using 2 bars allows you to get an even load on the axle. The clip isn’t that strong but the thing usually exits the transmission easier if the axle is pried straight. Be careful where and how you pry on the transmission case. Avoid creating spot loads on the case. Some areas can crack very easily if you pry directly on them. Use blocks of wood as needed to prevent this. When using 2 pry bars, this can be tricky. Tape the block to the bar so you don’t have to hold 4 things at once. Yes, there is at least one tool for this… The one I’ve seen is a 2-armed thing that connects to a slide hammer. Most people don’t do this often enough to need the tool.

Seals

Always replace the seal in the transmission anytime the axle is replaced! If the seal is old, it’s better to replace it even if you are reusing the same axles. Better to do it now than risk a leak after… If you score the mounting hole for the seal, clean the hole with brake parts cleaner and then apply a thin coat of sealer. For most scratches I like a paint type sealer like Permatex Super 300 or Balkamp Aviation sealer. If it’s a deep scratch then you may have to use RTV Silicone. Don’t get sloppy with the Silicone! A little bit goes a long way for this use. Rodney carries a combination seal and bearing that replaces the original style seal. I’ve yet to use them but everyone in the forums who has seems to like
them. (He also has replacement seals for his bearing sets. Now if you wreck a seal you won’t have to replace the whole bearing.)

Removing

Removing a seal often is no fun. The left seal is the worst. For the right axle, you can often just pry it out. But be careful not to damage anything. If it gives you trouble, then collapse the seal. To start, remove the collar that protects the rubber seal. It’s pressed into the seal. The metal is soft, you should be able to cave the side in then pop it out. Then you’ll be able to collapse the side of the seal and pull it out. Trust me… taking the collar out makes the seal much easier to remove. For the left side on the automatic… there is only one spot I found where you could get a bite on the seal with the thing in the car. Unfasten the mud skirt and go at it with a long screwdriver from the back. The screwdriver will be against the cradle as far back as you can get it. Tap lightly until the seal quits. Don’t pound it or you could chip/crack the case. It helps some if you collapse the inner part of the seal, where the rubber is held, and then cave in the outer part.

Installing

Driving the seals is a pain. The best driver I’ve used for these is a section of 2″ Schedule 40 PCV pipe. A regular driver, like the one from Lisle, worked ok on the right seal but won’t work for the left axle at all. You have to use pipe or a special tool for that one because the transmission shaft protrudes thru the seal. The PCV pipe fit these seals very nicely and won’t damage the guard. If you can’t get a perfectly straight shot at the seal don’t worry either… Just cut the end of the pipe at a slight angle. If you have a 2-3 pound mini sledge (AKA Drilling Hammer) use the side of the head. If you only have a small hammer, use a block of wood to spread the impact.

Selecting Replacement Axles

When buying new/rebuilt axles, it’s fairly common to have the wrong axle in a box! Lay the 2 shafts side by side and make sure they match before turning in the core. (Yes, I have had this happen. Extremely annoying.) Make sure new/rebuilt axles are the same length as the old ones! Never install an axle that is the wrong length. Too long and you could bind the inner CV. Too short and the inner CV will likely be torn apart. (This may not happen until you go over a large bump.) Also check outer CV profile. It must match the original. That means it has to accept the guard ring as well as fit the seal and hub. Don’t worry if the CV boots are a different type as long as everything else is correct. In fact, when you can find them, you want the ones with driven on neoprene outer boots. They are better boots and clear the hand brake cable much better than the thermoplastic ones that are clamped at both ends. There should be a metal guard on the outer CV that is just lightly pressed into place. This piece may need to be transferred to replacement axles. That guard protects the hub seal from dirt and so on. Try not to mangle it when you move it. It is better to work it off with a bunch of light tapping than try to get it off in a couple shots. No, you can’t use an axle from an automatic in a stick or the other way around. They won’t fit.

Extending CV life

There’s not much you can do that will affect the CV’s but this might help. Unless you live where speed bumps are common… Fiero outer CV joints spend nearly all of their time operating in over a small angle. If you give the wheels a few spins anytime the car is up on jacks it may help move the grease around in there. It might not help much but it sure won’t hurt anything. When you do this, listen for noises and feel for any inaudible pops that may be early signs of CV failure.

Axles for other transmissions

There have been many threads in the forums about this. Use the search function and search for axles to find the others.

Hub units

The hub isn’t hard to change. Again, anytime the axle is loose you should use a new axle nut.
One important note about buying hubs… the 84-87 hubs should come with a new seal loose in the box. This seal is driven into the knuckle to seal the axle. It provides additional protection for the hub cavity in the knuckle. Make sure the seal is in the box with the new hub. I don’t think you can get it separately. (Most hub units come with this seal.) These hubs should also come with a large O ring, usually it’s on the hub, that seals the front of the cavity in the knuckle. These seals are to prevent the hub from rusting solid in the knuckle. (The cavity isn’t totally sealed. There is a drain hole below the axle seal.) Before you knock the old one out the back, make note of its position and orientation. The new seal must be installed the same way. The new seal is driven in from the front (hub) side. I strongly recommend a seal driver for this. You’ll want the control the driver gives you to keep the seal straight.
Don’t forget to grease the seal before installing the axle. I also coat the inside of the knuckle hole with grease to prevent rust. You don’t need to gob it in, just coat things.
I haven’t been able to find a torque specification for the three bolts that hold the hub to the knuckle. Since they are the same size as the wheel lugs I ran them to 90-100 ft-lbs. I took a couple passes around to make sure I didn’t warp anything.

Driving the axle seal

Use of a regular seal driver will force you to remove the axle to do the job.
There is another way…
Measure the depth of the seal in the knuckle! The new seal has to be driven to the same depth. The axle usually has enough slack to push back out of the seal enough to work. Knock the seal out the back of the knuckle, bend/squash it out of round and then pull it out the front.
To drive the new seal…
Get a section of 2″ ID Schedule 40 PVC pipe and a straight connector. Glue the connector to the pipe. Use the connector end to drive the seal. A large hammer works better than a small one. Not because you need to beat the seal but because the big head spreads the load over the end of the pipe. I use a 3# mini sledge turned sideways for this.

You should grease the splines a little to prevent them rusting into the hub but don’t grease the areas shown above. You should also grease the axle seal to prevent wear.

NEW DRIVE AXLE TIPS

NEW COMPLETE DRIVE AXLES

Spicer Off-Highway Driveshaft Standard Product Catalog

Inner CV Joint

Outer CV Joint