Disc rear

[five7kid]

A disc rear has practially fallen in my lap.

My brother picked up a couple of Camaros, intending to make a project of getting one out of two. Well, his life circumstances changed, along with a dose of reality considering the condition of the cars, so he's decided to part out and divest himself of them. When he pulled off the aftermarket rims from one of them, he discovered it had rear disc brakes. So, after it gets to the junkyard, they're going to pull the rear for me.

No idea what gears it has or whether open or posi, but I figured that's secondary to the fact that it's got rear discs. We'll see if history proves that out. I've heard both good & bad things about 3rd gen rear discs, but this will be my first exposure to them.

[Chris 96 WS6]

Same rotors/calipers as 93-97 rear discs. Its really the exact same setup, PBR caliper, etc. etc.

Nothing wrong with them, they're more than adequate for 99.9% of people with these cars.

[five7kid]

What I recall hearing is the earlier version wasn't as robust as the later type. The car is an '82, I don't recall if rear discs were available that early. Actually, no idea what year the rear is, since the car also had a TH700 in it, which wasn't available in '82.

[Red Devil]

Chris, that's for '89-up. Before '89 you had to have the 1LE to get the same size, not sure if they were pbrs on the 1le though. I don't know, I never really paid much heed to 'em.

The earlier ones aren't too bad. Obviously it's not an aussie rear... unless swapped in, which could be the case since it has the 700. Not sure if disc was offered in '82 but wouldn't surprise me. :shrug: Worth a look and for stopping, better than drum typically. :) The '89 up got a (iirc) higher splibe count as well as the pbrs and larger rotor. On an odd note, I've never really run into e-brake issues with the '89-up ones, but have had a few pre-'89s show up with the cables frozen up.

[five7kid]

Looks like I'll be able to pick it up next week. We'll see what we've got then. I expect to have to do some sort of maintenance/repairs on it before it is worthy of being installed.

[five7kid]

Got it home yesterday. The axle code is 4PY, which translates to an '83 f-body 3.08 posi. No pinion seal leakage, it seems generally tight and quiet. I pulled the cover, it is posi and 3.08, so it probably hasn't been touched (even the gear lube looked like the original :D ).

The pads & rotors still look decent, but I'll need to go completely through the brakes as it is all pretty rusty. The park brake cables are toast, so I'll need to get new ones. Rebuild the calipers, turn the rotors or replace, new pads, new combo valve, weld the tubes, sand blast & paint the whole thing - then it'll be ready to install!

[talover111]

as for the rotors id go with new ones and for the rear oil id use royal purple its more expensive but its worth it

[five7kid]

I've been using AMSOIL lubes since 1983. Royal Purple is too expensive for my tastes. :D

[tuske427]

The part numbers on my '84 T/A were different for the drum rear versus disc rear on the master cylinder. I believe the proportioning valve was different, too. Later 3rd gen cars, however, came with the same master cylinder.

depending on what year car you put this in, you may need to install a different proportioning valve to keep this working optimally.

I'm not sure what year they went to common parts, but, It's worth looking into.

[five7kid]

From what I understand, the proportioning valves were different for 2 reasons: 1) different metering disk vs. drum rear; and 2) drum rear included a check valve in the rear brake line. Since I don't need the check valve, an adjustable proportioning valve should take the place of the factory valve nicely (at over $100 for a new factory style combo valve, the adjustable I have in the garage attic doing nothing at the present time is very attractive).

Also from what I understand, the difference in master cylinders is a slight difference in effort if you use the disk/drum unit with a disk rear. Nothing major or function-limiting.