[Orb]

I would check you ABS units. I take it that the problem is still there with new brake disk and pads but get progressively due pad disposition problem with ABS activate all the time. This important to note after the disk replacement did you still feel so issue. It should be silky smooth. The calipers float on pins so would check the bushing in them. If the pin/busing are severally worn then you can get this problem as they can stick and bind which cases a toe issue on the pads. Post a picture of you old brake pads so we can see if the wear pattern is normal. The wheel toe in/out looks normal given the cyclic loading from the brakes. Only suspension bushing to check is the large bushing on front tension.

Originally Posted by drhousedk

Hi

Car is a 01/2007 330d e91 231bhp.

For about a year, I've been experiencing quite violent brake judder when the brakes get hot. Only small vibrations when brakes are cold. Replacing discs fixes the problem for about 1000 miles. Those miles are totally smooth sailing. It's been quite a few sets of discs and pads now.

No particular event set this off.

Before all the guesswork starts - here's what's been done:

- Wheel balancing (Tried 3 different sets of wheels - flanges are clean and non-painted etc.)
- Different manufacturer discs (OE BMW, Ate, Brembo, Zimmermann)
- Different manufacturer pads (OE BMW, Ate, Brembo)
- All bushings and trailing arms has been replaced
- New Bilstein B12 Pro-kit suspension (dampers and springs)
- Top mounts (OE BMW)
- Wheel bearings including hubs (twice...)
- Alignment x 2, nothing to report
- Latest bet was a 335i brake upgrade - NEW! calipers, Brembo discs and pads were used. Went wobbly within 1000 miles as well. Thought that 330x24 -> 348x30mm would make a difference but no.
- Three independent shops checked the steering rack, and found it A-OK. No play in the steering column or shaft either.
- Proper break-in procedure as specified by Zeckhausen Racing on each set of discs/pads (can't reperform as the judder gets so violent after about 5 60-20 mph braking)

Calipers don't stick at all. I don't feel it as much in the brake pedal as I feel it in the steering wheel. Doesn't feel as violent through the seat.

Car doesn't have active steering. (Good old fashioned hydraulic belt-driven pump)

I'm quite anal about NOT keeping on the brakes after braking to a stand-still at the lights - I always put the car in park and let go off the brake pedal as soon as the car doesn't move anymore. Haven't been violent on the brakes on the 335i setup.

I've been thinking rear discs - but how on earth could they "steer" the front wheels so much, that it's visible on a slo-mo recording?