Okay... here is whats happening, I have an occasional rubbing sound coming from the rear of the car. (1980 SA22). The car has a GSL rear end with GSL disk brakes.

The sound can happen anytime under 30mph, doesnt matter if I'm turning or driving straight, it resonates through the entire vehicle so pinpointing it while driving is very difficult. if the sound happens, and I lightly pull the parking brake, it'll immdeiatly go away.

I've pulled apart the rear brakes, and cant find anything wrong... though I am a newbie with RX-7's so I may be missing something in my diagnosis.

When I pulled the rear brakes, I used anti-squeal on all the pads, and put a thin coat in between the rotor hat and the axle flange that it bolts to... the sound went away for a few days, but came back on a very rainy day.

Any ideas?

 

sounds to me like a definite brake problem...maybe your e-brake is adjusted a hair too tight...

 

Could you describe the sound any better? Is it a low pitch or high pitch? Vibration?

I usually get some weird rattling/vibrations when I back out of the drive in the morning, but once things warm up it goes away.

 

It sounds like something is vibrating... almost like a brake pad is just barely in contact with the rotor and is vibrating... however it is a lower pitch sound than what I would usually expect a pad to make... plus its very loud inside the vehicle from the sound resonating.

On another note, I found both my inboard pads have worn at an angle, so they are not hitting the rotors at 90 degrees. When I bought the car and started working on it, I found that the grooves in the rear pistons were not lined up 90 degrees off the braking surface like the manual shows. I pushed them back in and re-aligned the piston, but the pads are angled

Today, I hit a turn at a decent speed and heard a loud chattering, I think its coming from the parking brake

 

It sounds like something is vibrating... almost like a brake pad is just barely in contact with the rotor and is vibrating... however it is a lower pitch sound than what I would usually expect a pad to make... plus its very loud inside the vehicle from the sound resonating.

On another note, I found both my inboard pads have worn at an angle, so they are not sitting flat against the rotors. When I bought the car and started working on it, I found that the grooves in the rear pistons were not lined up 90 degrees off the braking surface like the manual shows. I pushed them back in and re-aligned the piston, but the pads are angled

Today, I hit a turn at a decent speed and heard a loud chattering, I think its coming from the parking brake

 

Whoops... didn't mean to double post that...

So any ideas? Anyone?

 

definitely the rear brakes. Mine do that on occasion when i'm backing up. Possibly calipers are not retracting all the way. Check your brake lines for and crimping, or collapsing. Make sure you've got enough brake fluid.

 

If nothing else, just spend most of your time driving spiritedly over 30 mph