Rear brakes rubbing after disc swap

[MegaHertz]

So I noticed some rubbing after I swapped the rear to one with disc brakes. Finally had some time today to get the wheels off and take a look. It seems the parking brake return spring is not doing its job and the inside pad rests at an angle. The pads are unevenly worn and the rotor is rubbing against the actual caliper and not just the pad. I'm hoping new pads will space it out a bit more and give the clearance needed. I lubed and worked the parking brake lever and it seems to move a bit more freely but still some rubbing (though not as bad).

Can the parking brake spring be replaced or should I look at replacing the calipers? It looks like it takes a good amount of tension to get that spring off and on.

[FirebirdGT]

Re: Rear brakes rubbing after disc swap

What year rear end did you install?
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[ssms5411]

Re: Rear brakes rubbing after disc swap

Was it a complete swap or just the rear brakes?

[MegaHertz]

Re: Rear brakes rubbing after disc swap

It was a complete rear end swap but there appeared to be some lines on the brake plate mounting point that would have indicated a brake swap at some point (also brake line mounting brackets were not bolted to the axle). I'm not sure of the year of the donor though the parts yard said it was from a bird and it has 3.42's with a torsen diffy. I'm pretty sure the disc brakes are 93-97 from the pics I've looked at compared to mine. The brake lines on the new axle lined right up to the junction block that came on my car.

[ssms5411]

Re: Rear brakes rubbing after disc swap

The mounting brackets should be mounted on the on the axle , theres no other way they go on.

[MegaHertz]

Re: Rear brakes rubbing after disc swap

I see where right where they should be bolted up - they just weren't and are just held on by brake lines. I need to find some bolts that will fit.

[ssms5411]

Re: Rear brakes rubbing after disc swap

They should be held in by 4 bolts on the axle, theres no way they are hanging there and working or half way working without support.

[MegaHertz]

Re: Rear brakes rubbing after disc swap

I was talking about the brake line mounting plates, not the calipers. The calipers are definitely bolted to the axle with 2 bolts a piece.

[MegaHertz]

Re: Rear brakes rubbing after disc swap

So i was feeling all productive this morning after an early haircut and during the ride home the brake rubbing was annoying and worrying me so I picked up some brake pads. I changed them out (personal best time of about 45 mins including digging out the jacks and what not from the garage). Took it for a test and the rubbing was still there. Since the rotor was rubbing up against the inside of the caliper I decided to try to shim it towards the center with some washers. I test fit with one on each stud but from test fitting it seemed pretty close to the caliper so I went with 2. Quick test and no more rubbing.

I've read about needing a shim when swapping to disc brakes and this rear appears to have had the brakes swapped. If that was omitted would it affect the centering of the rotor in relation to the caliper? Also I realize my lugnuts are now gripping less of the wheel stud because of the 2 washers, will 3/16" be an issue?

[MegaHertz]

Re: Rear brakes rubbing after disc swap

After some reflection I think I should have used the washers to shim out the caliper mounting bracket rather than the rotor. That would move the caliper inwards without reducing effective wheel stud length. I'm still reading up on this gm shim but I'm guessing that is what it does.

[FirebirdGT]

Re: Rear brakes rubbing after disc swap

After some reflection I think I should have used the washers to shim out the caliper mounting bracket rather than the rotor. That would move the caliper inwards without reducing effective wheel stud length. I'm still reading up on this gm shim but I'm guessing that is what it does.

http://forum.camarov6.com/showthread.php?t=63738

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[MegaHertz]

Re: Rear brakes rubbing after disc swap

Thanks for the link - I knew I had seen it around somewhere. Trouble is I'm guessing I've shimmed my rotor out 5+ times the .6mm thickness of the gm shim. Based on the depth of the grove in my caliper I'm guessing I need 3-4mm adjustment. I'm a bit over that with my washers but its not over enough to hit the outside of the caliper.

[MegaHertz]

Re: Rear brakes rubbing after disc swap

So far the washer shimming is holding up so far though its been maybe 30 miles since I did it. Still there is no rubbing of the rotor against the caliper frame but a weird metallic jingle noise when going around turns (a weird symptom I know - kind of sounds like a loose metal chain when jostled). I do realize I should be changing the shimming to the caliper rather than the rotor though ground frost has finally set in and that is where I draw the line at driveway repairs. (I do think I'm going to top off the diffy fluid before I head off for a 120 mile trip this weekend as the pinion is leaky - but that's maintenance not repair.)

[FirebirdGT]

Re: Rear brakes rubbing after disc swap

Do the pads have the anti-rattle clips/springs? I found they only come with factory pads, not aftermarket.

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[MegaHertz]

Re: Rear brakes rubbing after disc swap

Each pad had a metal clip on one side pointing away from the rotor surface. They actually got in the way and were bent as I pushed them into the caliper.