Help! Sudden Wobble

[Johno]

The car was working great and I'm on my way home. Nominal m3 experience. I push the brakes for the nth time on the commute and in a normal traffic situation and all of a sudden I have a shudder. This is at low speeds, and the vibration is significant. The steering wheel wobbles at least 1/2 to 1 inch during the braking. Again this came on all at once and I was not using the brakes heavy in such a way they could warp the rotors, or could they?

Any ideas what could lead to a sudden braking wobble to suddenly occur under normal driving?

Thanks!

[acetymekai]

I have had the same thing happen on occasion...i had it checked out at my mechanic...they tell me everything is fine...what the heck then?

but like i said...it only happens on occasion...98% of the time, no problem everything works perfectly...

for me it happens when braking on an uneven surface...it almost feels like the brakes are not grabbing for a moment...as Johno said...it feels like a "wobble"...

anyone?

///Ace

[OxfordM3]

Possibly a seized brake calipher.

[Johno]

What's the solution to a siezed caliper? Re-build or replace? Is relacing a caliper much harder than redoing the brakes, which I've done.

I jacked up the front and the right was dragging more than the front. But it is not extremely hot on either side. More like normal hot. Within a few minutes of having the front up and wheels off, the right was dragging less. It's OK to have a very slight amount of drag, correct? When I first checked out the right wheel rotation, there was more drag than I recall.

[hellrot325]

Lubricate the capiler guide bolts, they could be locking, especially if it's intermittant.

[Johno]

When I drove it last night there was no wobble. Very strange. Sometimes these cars seem very tempramental.

[BavarianThunder]

replacing calipers is really easy, its kinda expensive though. But when you get new brake pads, i recommend ceramic brake pads from raybestos, they don't produce any brake dust so your car/rims stay cleaner for alot longer.

[acetymekai]

When I drove it last night there was no wobble. Very strange. Sometimes these cars seem very tempramental.

i hear ya Johno...like i said...i notice it occasionally...weird...and I have almost brand new pads on my car...

next time i'm in with my mechanic i'll ask him about the calipers and see what he says...

[RotaryBzzz]

I believe there are a few threads about calipers locking up. I'd search this forum and the regular E36 forum as well. Perhaps even the General Maint forum.