Bimmer5project

so i finished replacing my front rotors and pads. while test driving i noticed a rattling caliper sound in the left , and a squak grabbing sound right before each stop in the right.

i had to leave out the location screws in the rotors, cause i drilled them out and had no replacement, but I've seen cars where they are sometimes left out as well, so I don't think that would be the problem. ( twas a bitch to put on though)

I also polished the whole caliper to a shine with a grinder and dremel. i was going to paint them after but the silver looks preety sharp. but i hope i didnt grind too much away...

btw while doing this i noticed they are ATE calipers if anybody was wondering. had no idea they came stock that way.

before i rip everything apart to examine the problem, can anybody guess what i messed up this time?


oh the rotors were slotted drilled and coated, was told not to clean the rotors with brake fluid before bedding them. which i found rather odd.

Hyper_545i

Did you reinstall the rattle clips properly? I would definitely get the location screws installed as well. Is the a vibration in the wheel while braking? Did you put the anti-squeal paste on the back of the pads, and the contact points on the caliper where the pad sits? Did you clean off the contact points with a wire brush? Did you clean off the caliper guide pins?

Bimmer5project

No rattling in the steering wheel while braking.

I did all that and more. One thing I noticed was the pins being very dry, even after lubing them with brake lube (silicon paste) a few days earlier. I got jammed cause of the seized location screw, so i put everything back together and went to the other side.

The pads did come with a silver paste, but I had silicon brake lube, so i used that on the back of the pads instead. is there a difference?

The location screws...One side I may have damaged the thread while drilling, so putting a location screw may not work. I don't know what that part is called or how much it will be to replace, if need be.

I guess I must tear into it again. I'm going to lube heavy, this is btw the 3rd time I will be taking the front brakes off.

twh

Guide pins do not get lubricated. They have to be smooth, no rust and the dust boot must be intact.

Rotors never get cleaned with brake fluid. I think you meant brake cleaner??

If you munged up a couple of threads or one side of the hole, the location bolt will still go back. Just clean up the threads with a wire brush and razor knife if you need to dig out anything.

I always use this brake lube on the rear of the pads and clips:
Permatex Ultra Disc Brake Caliper Lube (8 oz) 24110: You