Brake Caliper Replacement by Christopher Sass

All of our Fieros are getting older. And even if they have not traveled many miles, components deteriorate. Such is the fact with my own ’85 Fiero that has 101,000 miles. I use ‘high mileage’ in terms of the way most people use cars, but relatively low mileage in the life of a Fiero. Nonetheless, components can deteriorate even when a car is not driven. I recently experienced a failure of one of the front brake calipers. I do not know the cause(s) of the failure, I just know that it rendered my Fiero undriveable.

I soon learned that new calipers for the Fiero are no longer available from GM, so my choices were to use a caliper from another GM product or purchase rebuilt calipers. My Pontiac dealer refused to perform the work because only rebuilt units were available and independent shops quoted prices from $400 to $800 for the work. It became clear that I would have to do the job myself, and, faced with the prospect of replacing the brake components, I decided that this would be a good opportunity to replace the original brake parts with an upgrade kit. I purchased an upgrade kit that is available for 1984 through 1987 Fieros from the Fiero Store. The kit I purchased has vented front rotors, although they also offer cross drilled rotors and Carbomet pads for better wet weather braking, less fade, more braking power, and a great look, if your car is equipped with open wheels. The beauty of the kits from the Fiero Store is that they include everything you will need except the tools and the grease. And I mean everything. The kit I bought included the calipers, caliper brackets, wheel hubs, vented rotors, brake pads, inner and outer bearings, inner wheel seals, copper washers for the brake line, bleeder valve caps and retaining nuts with washers and cotter pins. I only had to make one trip to the auto parts store for a Torx fitting, brake fluid, and grease. And, by the way, the grease is cheap, so buy the best wheel bearing grease you can find. The tools needed for this project include 3/4" and 7/16” sockets, T50 Torx, C-clamp or long, sturdy flat blade screw driver, channel locks, pliers, 3/8” hex driver, 10mm open end wrench, and a seal installer or a plastic or leather hammer. The one additional item I needed was some WD-40.

Begin by placing the front of the car on jack stands using all the necessary precautions. The car should be in gear or park and the rear wheels should be chocked. While the kit includes instructions for installing the new parts, they do not provide any direction for removing the existing parts. They do provide an 800 number to call during regular business hours if you need help. The Haynes manual is helpful in providing instruction for parts removal. First you must remove the cover from the brake fluid reservoir and siphon about two ounces of fluid out. This is necessary to allow space for fluid that will be forced back into the reservoir when the caliper pistons are retracted. Make sure not to siphon off too much fluid because when you disconnect the caliper, you will lose some fluid. If the fluid level in the reservoir drops below the outlet, the system will take on air making the bleeding process more difficult. It is also a good idea to place a towel beneath the reservoir so that if any fluid does leak out, it will be caught by the towel, which is much easier to clean than the area beneath the reservoir.

To remove the calipers, you must push the piston back into the bore. The Haynes manual recommends using a C-clamp. If you do not have a C-clamp that will fit, you can use a flat blade screwdriver to force the piston back by inserting the screwdriver into the opening on the back of the caliper and forcing it against the outside face of the rotor. Keep an eye on the brake fluid reservoir during this process. As the piston is pushed back, the fluid is forced into the reservoir. Siphon off more fluid as necessary. Also, keep the reservoir covered during the project to prevent contaminants from entering the reservoir.

The Haynes manual instructs you to remove the bolt holding the brake caliper inlet hose fitting at this time. The problem with doing this step now is that fluid will be free to drain from the hose unless it is maintained at an elevation equal to or higher than the reservoir. This is not easy to do. Instead, I recommend that the bolt be loosened slightly, because it is easier to do while the caliper is still in place than once the caliper is removed; and then remove the caliper with the brake line still connected. Before you remove the caliper, have a platform in place to rest the caliper on. The manual recommends hanging the caliper from the suspension, but I found it easier to rest the caliper on an overturned bucket. Do not allow the caliper to hang from the hose. Removal of the caliper is accomplished by removing two mounting bolts accessible from the back side using a T50 Torx. Unless the car is on a lift, this procedure is performed blind, but it is not difficult. Once both bolts are removed, the caliper can be slipped off. If the piston is not retracted enough, the caliper will not slide off the rotor and bracket.

Next remove the spindle cap (by prying with a flat blade screw driver), cotter pin (using pliers), retaining nut (using channel lock pliers) and washer and then slide the rotor off. The OEM brakes have a one-piece rotor and hub. The replacement kit has a hub that is separate from the rotor. As soon as you have access to the caliper mounting bracket, spray the two bolt locations with WD-40 or apply penetrating oil to the locations. While you let this lubricant seep in around the bolts, take a wire brush to the remaining components and knock off the rust scale that has accumulated in the last 15 to 18 years. Then, using a 3/4 inch socket, remove the two bolts. Despite the years and miles, I was pleasantly surprised at how easily these bolts came free.

Install the new caliper brackets with the original bolts in the same manner that the old brackets came off. The brackets are conveniently marked “L” (left) for the driver’s side and “R” (right) for the passenger’s side. Pack the new bearings with grease making sure that the bearing is completely filled. You can do this by placing grease in the palm of one hand and pushing the edge of the bearing into the grease, turning the bearing as you go. When grease oozes out of the top of the bearing, you know that it is full. As an added measure, apply some grease to the outer face of the bearings. Then fill each hub with grease and install the inner bearing and the new seal. A seal installer is the preferred method, however if you don’t have one, place the hub on a soft material such as a towel or corrugated cardboard on a hard surface. Then with a piece of wood in contact with the seal, pound on the wood using a plastic or leather hammer. Check often to see if the seal is properly seated and use care not to bend the seal.

Slide the hub onto the spindle and insert the outer bearing. Place the new washer on the spindle and hand tighten the retaining nut in place. Install the brake pads into the caliper and slide the caliper into place. The brake bleeder valve should be pointing upward. Using the new mounting bolts provided, fasten the caliper into place. The Haynes manual instructs you to maintain a clearance of 0.13 to 0.30 mm (0.005 to 0.012 in.) at three locations between the caliper and the bracket. I found that the pieces fit snuggly and could not maintain these tolerances. It also appeared that these tolerances did not exist on the original installation from the factory.

There is one step that the manual and instructions do not discuss and is not necessary, however it will save you some grief. The outer brake pads have two small tabs that extend through openings in the caliper. Once the caliper is in place, these can be bent forward (toward the front of the car) by placing a chisel on each projection and striking the chisel with a hammer. Bending these projections will prevent the pad from rattling around when you encounter a bump and the brakes are not applied.

Now you can remove the brake line from the original caliper using a 10mm open end wrench. Cover the floor with a drip pan or other protection because as soon as you loosen the brake line, fluid will begin to flow.  Connect this hose to the new caliper using the new washers provided on each side of the brake line banjo fitting. Pay attention to the orientation of the banjo fitting. It has one side that is completely flat and one side that is flat until it approaches the line and then it bulges out with a radius. The side that is flat and without this bulge must be placed against the surface of the caliper to provide the proper seating of the banjo fitting. Also note, as I found out, brake fluid stings like a bee when it gets into an open cut, such as a skinned knuckle.

The retainer nut can now be tightened and the cotter pin installed. Reinstall the original spindle cover by tapping it into place with the plastic or leather hammer. I packed this cover with grease before installing it. Leave the wheels off for the bleeding process. You can now perform the procedure on the other side.

Unless you have a brake bleeder, you are going to need the assistance of another person to bleed the brakes. Bleeding is necessary to remove air that may be in the system. If you’ve been very careful, there shouldn’t be much air to contend with. Before you loosen the bleeder screw, smear some grease around the base of the screw to eliminate air from sneaking by the threads during the bleeding process. With one person inside the car, the brake pedal should be pumped to build up pressure and then the pedal should be held down. The second person opens the bleeder valve on the passenger side (the side farthest from the reservoir). Fluid will squirt out initially and then dribble out. The person in the car will notice the pedal sink down. With the pedal still depressed, the bleeder valve is closed to prevent air from entering through the valve. The process is repeated on the driver’s side. Repeat the process, alternating sides, until you are sure that all of the air has been removed from the system. Replace the wheels and take your Fiero for a drive.

I was pleased with the components and service I received from the Fiero Store. One of the hubs, however, had a misaligned stud, which prevented the rotor from being installed. I called the Fiero Store to report the problem and they told me that a new hub would be put in the mail that same day; and they did. I received the new hub four days later along with a mangled bearing. Luckily I didn’t need this bearing, but the Fiero Store will be made aware of these problems. I cannot complain because they did provide me with the necessary replacement parts and they were prompt and courteous.

The cost of this kit is $337.91 including postage. There is a $60.00 core refund for returning the calipers and caliper brackets if the calipers can be rebuilt. If you decide to get the next upgrade, the cross-drilled rotors are $75.00 and the Carbomet pads are $14.95. These costs are not in addition to the $337.91 because obviously you are substituting these parts for the vented rotors and standard pads. This project would have taken me about three hours including a half hour trip to the parts store to get grease, brake fluid, and a T50 torx fitting, were it not for the defective hub. For the master mechanics out there, this project could be performed in less time, however, even those of us who have never performed a brake job can complete this project in one afternoon.