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zach
07-20-2005, 10:33 AM
Fernando and I replaced the rear brake assemblies (pads, rotors, and calipers) on my 1998 M3 a few months ago. Everything was dandy for a while. Recently, however, braking on the highway results in SERIOUS steering wheel movement (quick back and forth) and general car vibration. I hate it.

Any idea what's up?

Thanks in advance. :oops:

FC
07-20-2005, 11:12 AM
Not cool.

Did you carry out a good visual inspection at all four corners? I can't imagine a caliper being loose. We tightened it pretty well. Granted we did not apply loktite, but still.

JST
07-20-2005, 11:20 AM
Fernando and I replaced the rear brake assemblies (pads, rotors, and calipers) on my 1998 M3 a few months ago. Everything was dandy for a while. Recently, however, braking on the highway results in SERIOUS steering wheel movement (quick back and forth) and general car vibration. I hate it.

Any idea what's up?

Thanks in advance. :oops:


It sounds like it may be significant pad deposits on one of the rotors.

Did you bed the pads after installing them? Do a series of high-effort stops from gradually increasing speeds? Most pads come with a sheet explaining how to bed them; otherwise, you can find FAQs on the 'net.

zach
07-20-2005, 11:27 AM
Fernando and I did bed the pads. I guess maybe I didn't do it enough...

I seriously hope nothing's loose.

In related news, I noticed this morning that after two hours on the highway, one rear wheel is hotter than the other....let's hope that one of the "new" calipers isn't fuxored. But, that's in the rear and shouldn't make the wheel dance.

I guess I should check the fronts.

bren
07-20-2005, 11:28 AM
You replaced the rear not the front? I can see the rears causing vibration but not yanking the steering...unless you are just using the steering movements to catch the rear of the car. Might be time to check on those front brakes :dunno:

zach
07-20-2005, 11:32 AM
You replaced the rear not the front? I can see the rears causing vibration but not yanking the steering...unless you are just using the steering movements to catch the rear of the car. Might be time to check on those front brakes :dunno:

The front rotors and pads and one of the calipers are relatively new.

This vibration only really happens at high speeds. :cry:

Nick M3
07-20-2005, 11:35 AM
You've also got that that one bad control arm...

rumatt
07-20-2005, 11:54 AM
You've also got that that one bad control arm...

Uh, that would do it. no?

zach
03-29-2007, 01:32 PM
Update: The driver side rear caliper locked up again!!!!! :irate:

FC
03-29-2007, 02:03 PM
Update: The driver side rear caliper locked up again!!!!! :irate:

That sucks. It may be time for a rebuild.:dunno:

John V
03-29-2007, 02:12 PM
Is it the caliper or the e-brake that is locked up?

zach
03-29-2007, 02:56 PM
Is it the caliper or the e-brake that is locked up?

I think it's the caliper.

zach
03-29-2007, 02:57 PM
That sucks. It may be time for a rebuild.:dunno:

I guess. But they were newly rebuilt when we installed them.

FC
03-29-2007, 03:22 PM
I guess. But they were newly rebuilt when we installed them.

I know. That's what makes this sucky. But there are only so many causes for it. If it isn't the e-brake, it has to be the caliper.:dunno:

zach
04-02-2007, 09:12 AM
Well, the caliper stopped sticking. I had the wheels off the car yesterday and everything seemed ok.

Interestingly, one thing I noticed was that one rear summer tire is FAR more worn than the other. Possible reasons for this are 1) one side in the rear is further out of line than the other; or 2) Kristin has been using the car for NASCAR races and not telling me.

Also, a word of warning to the NE 'mudgeons: now that I have the summer tires on the car, you can expect some snow.

rumatt
04-02-2007, 09:34 AM
Ugh...

If the caliper was locked up, that would make sense thought right?

FC
04-02-2007, 09:51 AM
Ugh...

If the caliper was locked up, that would make sense thought right?

Yes it would.

BTW... light snow for thursday 4/5.:mad: My credit card closes that day and I'll be ordering a set of PS2's.:cool:

JST
04-02-2007, 09:54 AM
Ugh...

If the caliper was locked up, that would make sense thought right?

A flat spot, maybe, but decreased tread the whole way around?

rumatt
04-02-2007, 10:04 AM
A flat spot, maybe, but decreased tread the whole way around?

"Locked up" was a poor choice of words. The caliper was stuck applying pressure, but it's not locking up the wheel.

Zach, which tire was more worn? It's actually not obvious. Under acceleration, the free tire will be working to push the car forward while the stuck tire will be fighting it.

While coasting, the stuck tire is working more because it's braking.




*cough* 335i lease *cough*

FC
04-02-2007, 10:05 AM
A flat spot, maybe, but decreased tread the whole way around?

To be honest, I don't know.:dunno: I could guess, but I'll just leave it at I don't know. I guess I'd need to know exactly what is happening to the tire when the caliper sticks.

zach
04-02-2007, 10:33 AM
"Locked up" was a poor choice of words. The caliper was stuck applying pressure, but it's not locking up the wheel.

Zach, which tire was more worn? It's actually not obvious. Under acceleration, the free tire will be working to push the car forward while the stuck tire will be fighting it.

While coasting, the stuck tire is working more because it's braking.

*cough* 335i lease *cough*

The bald tire corresponds to the caliper I thought was shot, so I guess that could be the issue. Would the LSD not keep one wheel from working and the other fighting?

rumatt
04-02-2007, 11:50 AM
Would the LSD not keep one wheel from working and the other fighting?

I guess it would try, but your brakes are stronger than the clutches in the LSD so your LSD loses. You may have toasted the LSd :ack:

There are occasional posts of RX8 owners destroying their LSD's by putting the doughnut on the rear. The LSD burns up while trying to keep the wheels spinning at the same speed. :ack: