Brakes still shudder at low speeds!!

[mike690003]

Hello Board,

After having new pads, rotors and sensors on my 300E, the brakes still "shudder" at low speeds. The mechanic pointed out to me that an electrical wire on my drivers side caliper was broken. Could that have an effect on my cars brakes "shuddering"?

Some things that come to mind are:

1. Bent spindle.
2. Mating surface on the hub was not clean when the new rotors were not installed.
3. New rotors have some run-out.

You might want to jack up one wheel at a time, remove the brake pads and use a dial indicator to see where the run-out is occuring, it's either coming from the rotors or spindles. Time consuming but that's about the only way I can think of is through process of elimination. Good luck

Also this wire you mentioned that was broken, are you referring to the wear sensor wire?

The mechanic pointed out to me that an electrical wire on my drivers side caliper was broken. Could that have an effect on my cars brakes "shuddering"?

If it's the front pad wear sensor wire, it ould not have any effect on the shuddering.

It's only an electrical sensor that lights up the pad wear lamp in the cluster when the front pad(s) are worn to the point of replacement.

Cheers.

[mike690003]

Could abnormal (too high or too low) brake fluid level make the brakes "shudder"??

not that I know of, never heard of that causing any shudder....

[Mike Murrell]

As pointed out already, less-than-perfect rotors could be the root cause.

How are your wheel bearings? Just a bit too loose can cause this sort of problem.

My experience with OEM rotors thus far has not been good. Many have showed up bad from the get-go.

After going through 3 sets the last time I changed them, I gave up and had a local machine shop turn them.

Some here believe that turning MB rotors is a no-no. MBDoc posted a good ways back that this is indeed a legitimate procedure. After the rotor turning, life was good and I was no longer spending week-ends replacing faulty rotors.

For all the anti-rotor-cutting types, look at what M.B.DOC had to say about it in this thread:

WARPED ROTORS

[haasman]

mike690003

Check your front suspenion carefully. The same thing happened with our 91 300E and after too much brake this and that, it turned out to be a bad tie-rod end.

A worn out steering dampener can give this type of symptom as well.

Keep us posted,

Haasman

[John Plut]

My wife's 300e developed a really bad rear end shudder when braking hard. I traced the problem to the rear subframe mounting bushings which had completely failed. Your problem seems to be in the front end though.

[SCOTTFISH]

I don't know this for a fact, but I have heard that abs problems can cause a shudder. Again, I don't know it to be truth, but it might be something to ask your mechanic.

[dakota]

Is it the ABS activating?