How do I fix this? Its been a long time since I looked at this but I seem to recall something about the axle moving ? This is on a 93 F-Body

 

Yeah, I had that happen when I redid my rear. The new Moser axles moved the rotor slightly in board, so whenever I made a quick turn, I would get just a faint hint of squeal as the rotor contacted the caliper bracket. I solved it by putting a thin stainless AN flat washer between the rotor and the axel flange (on each wheel stud) to space the rotorout another 20-30 thousandths. Worked great, no more squeal. You will need to verify which side is hittng (if not both) and try to accurately measure how much it needs to move. Add washers accordingly, and it's fixed!

 

I guess I should have explained, the axel does move slightly in and out, due to the gap of the groove in the axel for the c-clip. Some move quite a bit, others not so much. If you have the opposite problem from what I had, that is your rotor hits the OUTBOARD side of the caliper bracket, I think you can space the bracket out by adding thin washers between it and the attachment points on the rear end....I'll have to check on that. Been up since yesterday at 10AM, I need sleep. I think that's how it would work, though

 

thanks, I searched threads on here and found similar answers - one suggested that gm even sold a kit to fix it, and one said to grind down a spot on the caliper where the rotor hits. I think mine started acting up after I changed the brake pads. I assumed that the old pads left it more room to travel than the new ones. It is a really a nasty metal on metal noise. What are the sizing of those washers you used?

 

Some light grinding would probably work fine, as long as it's minimal. Are you sure the caliper is hitting, or is it the caliper bracket hitting on the rotor? The caliper can't really hit the rotor, the problem is the bracket itself. The washers I used were 7/16" or 1/2" (whichever size the wheel studs are) and are the thin SS AN type, they spec around 55-60 thousandths thick

 

Mine did this when I switched to ceramic pads. I quickly went back to semi-metallic. I have not touched them since.

 

The shim worked for me - only took one per bolt, about a 15 minute job including getting up and down on the jack.