The 87 GTA I bought had some of the worst brakes I had ever seen. I was replacing the rotors and pads all around, when I hit a snag. The rear discs wont come off. Also, the calipers are on the rear of the driver's side disc, and the front of the passenger's side disc. Is this normal? The front rotors came off without a hitch and the new ones look great, but the manual says the rears will pull off once the caliper is removed. They don't. I was able to get the driver's side caliper off, but the passenger's side won't come off - mainly due to the fact that I think it is on backwards (there is almost no room to get the lower mounting bolt off). I tried heat, PB Blaster, cursing, kicking, nothing seems to work to remove the old discs. Can anyone offer advice on removing the discs and confirm if the calipers are supposed to be on alternate sides in the rear? Thanks

 

Yes, it's normal for the passenger side caliper to be on the front side. GM did that so they could use the same caliper on both sides.

 

Undo the control arm at one end and rotate it out of the way to remove the lower caliper bolt. I think you can actually wiggle it out without disconnecting the control arm, but I don't think you'll be able to get it back in. Save the agro and disconnect the control arm.

As for the disk, tap around with a BFH.

 

And a piece of wood.

Ed

 

If that doesnt work, and its a 9 bolt rear (likely is), you can use a thin head 9/16" wrench or grind one down and remove the bolts holding the axle and pull the whole axle out. There are 3 holes in the axle flange and you can hammer on those to help persuade the rotor off the axle.

 

Thanks for the tips...I'll give them a shot. A couple of other things - I noticed the rear caliper pistons were solid. My experience has been solid pistons can't simply be compressed, they have to be twisted in, confirmation on these? Also, being solid pistons, the brake pads won't work since they have the spring clip on the back of the inside pad that slips into the hollow piston. The front/rear pads are identical part numbers, though. Has anyone else noticed this? Just remove the spring clips and grind them smooth or what? Thanks

 

Front and rear pads aren't the same part number.

 

Yes but the front pads can be used in the rear with the early iron caliper setup. The only difference is a small part of the unused squeal tab on one end of the backing plate is trimmed off. It just makes it easier to install.

 

Yeah, I checked it out today, you're right. When I bought them, the guy gave me two front sets instead of one of each; so I'll need to get those exchanged. Any word on the pistons, though? Can they just be compressed? I've already ruined a pair of calipers that way, so I'd prefer to not repeat history on that one.

 

The rear pistons need to be screwed back in, not pressed.

 

I think the only physical difference between a front pad and a rear pad is that the rear pad has a little pin on the backing that fits into the notch on the rear piston. The pin is to stop the piston from spinning. Most replacement pads have the pin, so they can be used for front or rear.

The stock front pad is suppose to be semi metallic while the stock rear pad is softer.

 

Best way to get "fused" rotors off with as little potential damage is air hammer all the way around the mounting face where the lug studs are. it'll loosen up in no time.

 

Looking at them, the fronts have a spring clip which is supposed to slide into the hollow piston, whereas the rear calipers have a solid piston, so they won't work that way. Also, when I was messing with the "rear" pads, the wear tab caused the caliper to not go back together. It was just sticking out too far. So I'll need to exchange them anyways...but they are nearly identical in shape, size, and fit.

 

With replacement pads, that front spring clip is removable so the pad can be used in both the front and rear calipers.

Now that you mention it, I think I just broke the wear tab off for the rears.

 

on my factory 9 bolt, i never had to remove the wear tab.

 

This is a front pad. The only difference in this and the rear is the red line in the photo where the arrow is, that part is cut off. It will not prevent you from installing the pads into the caliper or the caliper onto the car but you'll have to rotate it slightly rather than slide it straight on.

 

I don't know if anyone is reading this thread anymore, but I figured I'd add what I found. The pistons DID NOT need to be screwed back in, they could be pushed back in...also, the parking brake HAS to be removed from the back of the caliper before the piston can be compressed. Hope this helps someone.

 

I am going to do my rear pads this weekend. Do I need a special tool to screw the piston back in, or just a screw driver? Has anone else just taken the rear e-brake portion off of the caliper to compress it and then put it back together? If so did the e-brake work fine after this was done?

 

You only need a large C-clamp to push the piston back in, or a hefty wrench can be used. You can use a brake piston compressor kit, which uses the holes/grooves in some solid calipers to better grip them, and is similar to a C-clamp, but those are generally used when it has to be screwed in. My E-brake still works just fine. Hope this clarifies some stuff.

 

I have just seen posts written that state unless they are screwed back in, that you will destroy the caliper. Mine look different than the front. The piston is solid, it isn't hollow behind the pad. I read through my Haynes manual last night, and it said I have to get a tool to screw them in. I would hate to just compress them and destroy the calipers if mine are different. I think the newer PBR (if that is the correct type) calipers are different than what I have.

 

Yeah, I probably read all of the same posts, and that is why I went and bought the caliper compresing kit, but it turns out, I didn't need it. My brakes sound like the same as yours - solid in the rear, hollow up front. I can tell you that you better not try and compress them with the E-brake still attached, because it won't work and you can ruin the caliper. I have a Haynes manual, but it didn't specify to turn or push. However, I now also have a shop manual (very useful) that specifies pushing them in with a C-clamp. The part # on your rear calipers and mine are the same, so I'd guess they can be pushed in. If in doubt, once the equalizer nut for the E-brake is loosened, the piston wil compress very easily...only moderate force is required. If it is not budging, get the kit. You can rent it for free at Autozone; I bought mine for like $15 at Harbor Freight.