Rumbling Brakes

[Waratah]

Picked the car up yesterday from MB, Chelmsford - All Sorted - Again

New discs and pads on the front replaced under MB parts warranty.
MB engineer claimed the discs had warped in about 500 miles ' could be a faulty batch', although in his 20 yrs experience never had this before.

Funny thing is on 3 rolling roads (2 third party, 1 MD Dealer) the fault was diagnosed as being the rears, however twice the rears were replaced only to discover that the probelm was not solved
Both Tec and MB Chelmsford reverted to putting the old discs back on the rear and replacing the fronts.

Don't know why but i'm yet to be convinced there isnt something else at fault which caused the disc to warp.

 

[lynall]

I'll bet none of these disks are actually warped, more likely they have uneven friction material deposits which can be scrubbed off.

There are only two ways to warp disks.
1. Cane the nuts off the brakes then sit with the brake on hard, or
2. get the disks very hot then douse with water

3. fitted incorrectly.



Lynall

 

[Waratah]

Picked the car up yesterday from MB, Chelmsford - All Sorted - Again

New discs and pads on the front replaced under MB parts warranty.
MB engineer claimed the discs had warped in about 500 miles ' could be a faulty batch', although in his 20 yrs experience never had this before.

Funny thing is on 3 rolling roads (2 third party, 1 MD Dealer) the fault was diagnosed as being the rears, however twice the rears were replaced only to discover that the probelm was not solved
Both Tec and MB Chelmsford reverted to putting the old discs back on the rear and replacing the fronts.

Don't know why but i'm yet to be convinced there isnt something else at fault which caused the disc to warp.

Here I am again
Looks like the second set installed a few weeks ago are now warping.
I am starting to pull my hair out on this one.

What could be the causes?

 

[johnsco]

Unless you've been driving it and braking like a hooligan, I don't know how it's possible to warp discs.
Incorrect installation would be my guess - But even that's unlikely on each and every occasion.
How are they diagnosing warped discs ?
If they use a dial-gauge and spin the wheel and detect run-out, this could just as easily be poor installation causing the run-out as a warped disc ... More likely, in my opinion.

 

[JonMad]

I'll bet none of these disks are actually warped, more likely they have uneven friction material deposits which can be scrubbed off.

There are only two ways to warp disks.
1. Cane the nuts off the brakes then sit with the brake on hard, or
2. get the disks very hot then douse with water.

Warped disks will be felt through the pedal as opposed to making noise, due to the disk pushing the pads back.

My brakes have started rumbling after a trackday. I hope it's the 'uneven deposits' rather than warped disks. I don't think I did (1) or (2).

I can't see how your discs would warp with just normal use, esp. after only a few miles.

 

[welland99]

Here I am again
Looks like the second set installed a few weeks ago are now warping.
I am starting to pull my hair out on this one.

What could be the causes?

I don't think you have commented on your driving style yet. Do you make the brakes work hard, or do you give them an easy life?

 

[Stratman]

Warped discs and other brake myths

 

[Waratah]

I don't think you have commented on your driving style yet. Do you make the brakes work hard, or do you give them an easy life?

I am very easy on the brakes, I drive to maintain a low fuel consumption, so I very rarely brake hard!

 

[Waratah]

Well, I thought I may give you an update:

Since my last post the Car has been in a further 3 times, the last 2 visits to MB Dealership.
I have now had a further 3 sets of discs and pads fitted to front, new discs and pads on rear, n/s flange adjusted and n/s brake calliper cleaned up due to some corrosion!!!!

Its in again this week - and they have now diagnosed i need a new o/s calliper, new discs on front and pads.

We'll See?!

 

[alexander patie]

I'll bet none of these disks are actually warped, more likely they have uneven friction material deposits which can be scrubbed off.

There are only two ways to warp disks.
1. Cane the nuts off the brakes then sit with the brake on hard, or
2. get the disks very hot then douse with water.

Warped disks will be felt through the pedal as opposed to making noise, due to the disk pushing the pads back.

And this was Dieselman's last ever post - shame.

Anyone know why?

 

[alexander patie]

someone must have a clue, dieselman was such a proliferous and knowledgeable poster. why has he gone?

 

[momomo]

I would love to know as well alexander.

 

[alexander patie]

and he has tried to get back on the site, seems he has had a lot of technical problems getting access. read here... Mercedes-Benz Owners' Forums

 

[momomo]

Alexander ive spoken with him quite a while back actually about this, before he started that thread...

 

[kamalpatel12448]

I've had disc that had rusted from standing in the rain for a week and they squealed until cleaned properly. Rumble must be a friction related issue - at a guess how about rear disc as this wouldn't manifest via the steering wheel.