Ever since having after market rear pads fitted, my 03 MCs now 'squeeks' with every rotation of the rear wheels. If I lightly apply the foot brake, or the hand brake, the noise stops. There is no noise during normal braking.

I took it back to the BMW/Porche specalist that fitted the pads, and they said the calipers where binding and I should have the dealer replace them under warrenty. So I go to the dealer and they say there is nothing wrong with the calipers, it's the after market pads that are making the noise ..... grrrrrrrr.

So tonight I jacked up my car and spun all the wheels. I expected the rears to spin more easily that the front (since the front is connected to a drive shaft) but that was not the case. A good spin on the front and the wheel turns 2 1/2 revs, the same amount of push on the rear turns the wheel only just past one rev before it stops.

Anyone have any thoughts?

I have read people talk about a spin test, but how easily is the wheel supose to turn?

Anyone ever heard of after market brake pads causeing the wheels to squeek?

 

depends on what kind you got, and what you plan to use the car for.

Calipers move the piston back by useing a square o-ring to seal the piston. It shears before sliding, and when you take your foot off the brake, this shear backs off the piston. But wait, there's more.

Our cars use what is known as a floating caliper. It slides on those metal shafts that go to the pad carrier. So to really get the pads off the rotors, you have to move the piston back a bit, AND slide the caliper over a bit. Hmmmm. Nothing there to do that... So one of the pads tends to kiss the rotor a bit.

But wait, there's more STILL. The parking brake cable housing is pretty stiff. It puts some force on the caliper (at least mine did). Now the floating caliper is on these crappy rubber bushings, and they deform. So now the poor little o-ring has to move the piston back, with enough room for the caliper to move a bit, and compensate for the crappy rubber bushings..... Poor little o-ring!

So, yes it's an issue with the calipers. And yes, it's normal. Not good, but there's nothing to be done about it.

First off, I'd get some of the metal caliper bushings. Only $120 for all four wheels. Then I'd just live with it, or go to another pad compound. If you're really hard core, get a big brake kit with fixed calipers. Then pistons are on both sides, and each sides piston(s) will be pulled back.

Matt

ps, sorry for the long winded answer.

 

Thanks for the info, that does help a lot to understand what going on. So are you saying that having the rear wheels only spin one turn (when the fronts will spin two) in normal becuase of these caliper issues?

No I am not hardcore at all, I don't even know what make the pads are, I only went to this shop because thier price was cheaper than the dealer. ($325 vs $450 for rear pads and disks) I let them fit what ever they recommended. I don't need anything fancy, I just want the damn noise to stop. My wife says she won't ride in the car again until it get "that embarresing noise fixed".

Dealer says that if he fits MINI original pads then the noise will go away, but I don't trust them. (last visit was for an oil change and they could not even get that right, forgot to reset the service computer)

 

AM pads can easily be the cause of the squeak.
but...
the rear calipers also have a screw-mechanism that holds the piston in place when the park brake is applied.
rear brakes can be nasty little buggers, if the shop that replaced them did it incorrectly, they could have seized the piston or stripped the screw.
did they try to re-use the springs and shims? Did they have competent mechanics?
need to hear more about the symptoms to help diagnose an answer. could also be the rotors, if they were also AM, or if the shop turned them, or if they weren't replaced at all.
you could try removing the rotors and swapping sides
sounds funny, but it may work.
GL

 

They replaced the rotors as well with AM (but dealer says it the pads that are the problem not the rotors)

I went to this shop becaase I assume they know what they are doing. (my dealer does not know what he is doing, that's another thread) They are a high end service shop, thier primary mark is Porche and they do some AM tuning on Porche and BMW. Shop is always full of BMW, Porche (from 70's to current) Merc's and the occasional Jag, Audi, Range Rover, Alpha. Basically all European high end stuff.

I don't really have the skills to work on the brakes myself, what I need is to figure out who should be resolving my squeek, 'cause dealer and service shop are just pointing at each other right now.

The Squeek will go away for a day if I wash the car (which of course involves blasting the wheels with a hose) or if it rains. But if the weather stays dry it seems to get worse and worse. It's a regular squeek squeek, in time to the rotation of the wheel, When road is dry, it does it all the time as I drive. On the freeway I have to have the audio uncomfortably high to drown it out. Only time it stops is if I apply the rear brake (foot or parking).

If my calipers are binding (for what ever reason) then this should be evident by how easily the wheel spins right? But I don't know how easily the rear wheels should spin, seems like they should spin more easily than the front (no drive shaft) but I don't know if that's right .........???

Help

 

I can think of a few thing s to try to isolate the issue to either the caliper or the pads/rotor. you could try driving with the park brake on slightly.(enough to slow the car/stop it from rolling away, not hard enough to stop it under any power) drive a bit and see if the squeak stays away. this would point to the caliper as the root cause of the problem. if the squeak returns after only a few miles, the problem is in either the pads or the rotor. without really getting under the wheel, and looking/listening; it is a hard thing to diagnose. the anchor/adaptor/bracket that holds the caliper to the knuckle could be loose as well, or a shim/spring could be sliding around.
the rotors could have excessive runout, too.