Schulminator

So I installed racing brake 2-piece f/r rotors and pads a month or so ago. Did a complete fluid swap with motive bleeder and had no issues during the install. Since the install, I'm getting a weird noise from front D/S, it goes away when I apply the brake slightly and it's the loudest when cold.
Jacked it up and spin the wheel and it's like the piston(s) are not retracting and the pad(s) are making slight contact with the rotor only in one section of the rotor. I removed everything again cleaned the hub to ensure the rotor was flush and still making the same noise. Could it be a stuck piston, air in that particular caliper, or a warped rotor? Any input would be appreciated.


Dan

Carbon Dated

Total guess here, but I would say a sticking piston.

Schulminator

I was thinking the same, but it only seems to make contact with the rotor in a small area when spun. Makes me think maybe the rotor has an excessive bit of run-out.

Thrilla

Check if there is play between the rotor and the hat. Make sure it's torqued correctly.

brad65ford

Just did my front brakes today So far so good but didn't' bleed or replace fluid. Wondering what you use to compress the pistons? Any chance they were compressed on an angle damaging the seals? Are you leaking brake oil? Wondering if it air bound also.

Schulminator

No visible leaks on that caliper, I pulled that side back apart after a couple weeks of driving. Thinking maybe I'll bleed that side again, if that doesn't work maybe have the rotor lightly skimmed at my local machine shop.

computertom

Have you pinged Racing Brake to see what they recommend?

Alex.currie44

With you on that. Doing pads and rotors without servicing the calipers can and usually does lead to issues. The slides at least need cleaning and lubricating.

Schulminator

On past cars with multi-piston calipers, I've never had any issues when changing pads or rotors. I didn't think you could really "service" them, as either you rebuild them or not. There are no visible leaks from any of the pistons, but maybe will look at rebuilding them with new pistons/seals.

Alex.currie44

I am having a squealling issue with my car and spoke with my SM at my dealer who I trust implicitly having worked with him for 9 yr and he was clear that two factors could be causing it since we know there is a lot of pad left.
One was glaze on the brakes because we tend to not use the brakes hard in normal day to day driving and they glaze. The other is since my car was sitting for 9 weeks while I was down south the crud on the slides may be hardened up and the calipers need to be serviced which is basically a cleaning of the slides and rails. Just saying. I also like the idea that there may be a bit of rotor warpage.

Schulminator

Our calipers are fixed, there are no slide pins. The only movable parts are the actual caliper pistons. Sent a note to RB for their thoughts as well, as I don't want to throw $$ at it if it's not going to fix it. Everything was nice and quiet until I did this swap

Schulminator

Update: I installed RB's complete front caliper rebuild kit today, new pistons and seals. All seems to be nice a quiet now, sanded down pads and did the bedding process again. Thanks to all for reply, this forum is very helpful.... for technical stuff.....