My 1987 535i has had a brake problem since I bought it 8 months ago, and I think I may have to take it in to the dealer for repairs, since nothing has worked. Most people don't even understand my description of this problem.

When I hit the brakes to slow down, especially at slower speeds, there's a loud shimmying noise from the front rotors, that feels like the pads are slipping all over the rotors. Besides the disturbing noise, it detracts from the braking power.

I have replaced the upper and lower control arms, center link, and idler arm, and tightened up the steering box, to no avail. The front suspension has since been aligned. Also, there are no leaks in the power steering/brake booster system.

The front bearings grind when I spin the wheels by hand. And, the rotors and pads are cheap. And, when I replaced those, I didn't return the little allen-bolt to the rotor, since someone told me those are just used to keep the rotors on the axle on the assembly line. These may be the problem?...

My repairs have tightened up the steering a bit, but have made no difference to this braking problem. Any ideas, or solutions, would make a huge difference, and would be much appreciated!

Thanks, iain

What do mean when you say the rotors and pads are cheap?

The shimmy felt through the steering is almost always warped rotors. Always replace the allen bolt to initially secure the rotor to the hub. Additionally, proper torque of the lug bolts are very impotant.

Are you doing the work or is a mechanic doing same?

Thanks for the response. What I mean is that I bought the rotors and pads only with (low) price in mind, so when I buy another set I'll probably go with Metalmaster or other higher-quality brake parts.

It seems that the lug nuts should hold the rotors on fine, in lieu of the allen bolts.

I have done the work myself, except when I couldn't get some frozen bolts off. At that time, I c/o this "pad-slipping" problem, and the mechanic turned the rotors, which I've heard should never be done on BMW's, and which didn't help the problem at all.

Please help!

-another amateur BMW mechanic,
Iain