Brakes are real easy to check.
Pull the wheel off and look at each end of each pad. | |
The four pads on each end of the car should be worn evenly, inside and outside of each caliper, left and right wheels. Expect the fronts to wear faster than the rear brakes. | |
The service manual says to replace if there is less than 1/32" of pad above the rivets or visible at the end of the pad. I think this is a stupid spec, since you can't see the position of the rivets or if your pads have them (the stock ones on my car didn't). | |
The rivets on a set of replacement pads stick up 3/32" from the plate which makes the suggested spec 1/8" from the plate. |
If you have to replace the pads, the front ones follow the usual procedure but the rear ones have the parking brake adjuster which requires a special tool (cheap) to screw it in.
If you need to replace the pads, you might want to get a copy of the appropriate service manual pages for your car.
From: Bill Fuhrmann
You have to remove the brake pad slide pins on the 88 Calipers to remove the pads. There is a special tool for this, but most people just drive them out with a punch and nail. Put in NEW slide pins when you replace the pads - if the old ones are even slightly bent you will have brake problems. The GM part number is 3487475, includes new springs and are about $10.00 per kit. You will need 4 kits. If you don't want to spend this money, at least roll your pins on a piece of glass or mirror before reinserting to make sure they are straight.
From: Randy Agee
From: Sketch
Changing the brake pads on a 1988 Fiero requires the use of a special slide hammer to pull the spring pins out. I priced the hammer from the local dealer ($275) and decided to try something else.
I attempted to drive the pins out with a drift, but they should be driven out from the backside, which makes it difficult to get a punch and hammer in there. So, I made a single-use pin puller using a 6-32 threaded rod about 8 inches long. If you want to try this, follow these instructions.
Take five or six 6-32 nuts and lock them on one end of the threaded rod. Take them to a grinder and round them off to a little less than 1/4" diameter. Use a couple pair of pliers to remove the rounded nuts and slip the threaded rod all the way through the spring pin from the outboard side of the caliper. Then screw one or two of the rounded nuts onto the threaded rod on the inboard side of the caliper. This is similar to the GM tool J36620 as seen in the 1988 Pontiac Fiero Service Manual on page 5B10-3, Figure 3.
Now take a 1" long tube with a 5/16 I.D. or a deep 1/4 drive socket and slip it over the outboard side of the threaded rod. Next, place a number 8 flat washer on the threaded rod against the tube.
Thread a normal nut on the threaded rod all the way against the flat washer. Slowly tighten the nut to pull the pin out of the caliper. It would be a good idea to lubricate the nut at the washer and threads to reduce the amount of thread wear. As I said, this is a discardable tool that will let you pull 1 or 2 pins. After each pin is pulled, move the rounded nuts further up the threaded rod so that the tightening nut will contact new threads each time. Also, use a new nut each time.
If the spring pin doesn't begin to move, tap the inboard side of it with a hammer and drift. You should see the pin jump a little bit. Mark it with a magic marker, if necessary, so you can see it move. Tighten the nut about a half turn and then tap the spring pin again. Repeat the tighten/tap procedure until the pin is out of the inside caliper hole, and yank the entire assembly completely out of the caliper. Some silicone spray on the spring pin will also help it slide out. Go easy on the 6-32 threaded rod or the threads will strip.
Now, lose the spring pins -- that's right, throw them away. When the brakes are applied, the pads rest up against the caliper housing which transfers the load to the caliper mounting bolts. The spring pins simply retain the pads in the caliper, and do not carry any of the braking force. I think pins were used because they are relatively cheap and are easy to install on the assembly line.
I replaced the OEM spring pins with 1/4-20 X 4-1/2" long stainless steel hex bolts. I cut the bolts to 3-7/8" long, and drilled a 1/16" hole about 1/4" from the end. Slip the bolts through the caliper and brake pads as per normal, and put a cotter pin or spring clip through the little hole.
Now, to change the pads, simply pull the spring clips, slide the bolts out, and remove the pads. Assemble in the reverse sequence.
I used stainless steel bolts because I couldn't be sure that plain steel bolts wouldn't rust. Maybe painting with high temp engine paint would keep them clean.
If you don't want to cut and drill the bolts, get some that are 4" long and put lock or jam nuts on the end of the bolts. However, the nuts make it difficult to bleed the system because it's harder to get a wrench on the bleeder screw.
Now, I'm not an automobile engineer, have never designed braking systems or any other automotive system. I don't work for, and have never worked for, GM or any other car company. Therefore, I disclaim any results you may have with this modification. I assume no liability if you choose to make this modification to your car. You assume all liabilities. I make no guarantees. So, you're on your own.
From: Larry Mazza
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