Brake peddle judder

[sirmatt]

Hi All

I'm new to the forum, but I'm hoping you can help me.

I have a 4 year old 320 CLK, last month it developed a judder on the brake peddle when braking at higher speeds 50 + MPH, I assumed I had warped front brake discs so I replaced them and the pads(fun job !!!), unfortunately the judder remains. In desperation I've just ordered a set of new rear discs hoping this may sort the problem, but I would be grateful of any other thoughts.

The symptoms are most noticeable at high speeds, but I am now experiencing them at lower speeds to so it's getting worse, there is minimal wobble on the wheel, the car still brakes in a straight line there is no pull. Also you only feel the judder when you apply the brake more firmly (it's not ABS - it definately feels like warped discs).

I'm hoping changing the rears will sort the problem, but any other thoughts would be helpful.

Thanks

Mike

 

[scotth_uk]

Slightly off topic, but how's the wheel balance?

 

[Brian WH]

Slightly off topic, but how's the wheel balance?

Not off topic at all, very relevant and worth checking first before replacing anything else.

Moving to brake section.

 

[jgevers]

Most likely warped rear discs. Check run-out

regards,

Job

 

[guydewdney]

dont forget to clean the surface that the disc bolts to.. when a wheel is removed, the disc is potentially loose, and can have a bit of crap fall behind it, causing slightly 'warped' or wobbly disc..

 

[Will]

You could check the rear discs with a dial gauge before you spend money replacing them (that is, unless they are badly worn and need replacing anyway!)

I'd check other cheap and easy things first too, like Scott said, wheel balancing, and maybe wheel bearings etc too?

Good Luck,

Will

 

[sirmatt]

Thanks for the replies, the tyres are reltively new at the front (less than 1,000 miles), I'll get them checked though. I had thought about the wheel bearing, but I would have thought that I would have got some noise as well and it's smooth and sounds normal. I made sure the mating surfaces were nice and clean when I put the new discs on, so I think that bits OK.

I'll have a go at the balancing and then if that fails out comes the trolley jack and rubber gloves !!!!.

I'll keep you updated !!

Thanks again

Mike

 

[Satch]

Read this first!

http://www.stoptech.com/whitepapers/warped_rotors_myth.htm

 

[scotth_uk]

Personally, I have rarely been satisfied with wheel balancing and it has caused me a lot of irriration over the years. Many places do not care for their machines and their balancing ability is way off.

I have argued, argued and argued some more with some places and they've tried a few times with no success. I've then had somewhere recommended, popped down there and had the balance corrected immediately.

I had a problem with shudder on my Micra at about 60mph for almost a year before I worked it out. I replaced everything, assumin that the brand new wheels and tyres were correctly balanced - they were not!

 

[sirmatt]

Just a quick note by way fo an update to the problem.

The new rear discs and pads arrived yesterday and I fitted them yesterday afternoon - problem solved !!!!!!. Have to say what an easy job as well.

Anyway the problem wasn't run out on the rear discs, the rear side of both discs had basically falllen off in chunks, because of the rear dust shield and the position fo the caliper you could not see this until the disc was actually off the car.

Anyway if you experience judder on the pedal worth having a look.

All the best to the rets of the forum for Christmas and the New Year.

Mike

 

[Dieselman]

Anyway the problem wasn't run out on the rear discs, the rear side of both discs had basically falllen off in chunks, because of the rear dust shield and the position fo the caliper you could not see this until the disc was actually off the car.

Not uncommon due to the rears not doing enough work to keep rust off the disk.

You need to bring on the traction control more, that'll keep them clean.

 

[Satch]

Not uncommon due to the rears not doing enough work to keep rust off the disk.

You need to bring on the traction control more, that'll keep them clean.

And then you will have people wondering why the rear pads and disks are wearing out as fast as or faster than the fronts. Just like E55 AMG owners.