Warped Discs?

[junglie]

I have recently purchased a Mercedes Benz C320 CDI Estate (2005) with 60k on the clock and FMBSH. Discs and Pads were recently changed and it has been fine. I left the car in a carpark near the sea for 3 weeks whilst I was away and obviously there was some build up of rust on the disc surface.

Normally you have some dip in braking performance while the pads scrape off the coating and then you are back to normal. Now, when I brake, I get a grinding sound although no steering wheel shake and braking performance seems to be slightly degraded.

Is this a case of a warped disc or something more sinister?

[*Al*]

Try some heavier longer braking stops. They should improve.

[pist nbroke]

Discs warped through leaving the vehicle over a period of time, i would say no.

To warp a brake disc it would need to be exposed to extreme heat. For example an emergancy stop from a highish speed.

As you say, probably just a build up of corrosion on the surface of the disc. Drive it for a while with slow and gradual brake application if possible. Alternatively the parking brake shoes on the CLK (as with all Mercs) run on the inside of the rear discs maybe these are slightly siezed.

[junglie]

I have tried a few high speed stops and it does not seem to be making any sort of improvement. No major scoring noticeable so I can't think that there is any debris caught between pad and disc.

Annoying on an otherwise great car!

[anonymous-user]

This seems to be a good read -

http://www.stoptech.com/tech_info/wp_warped_braked...

and maybe this one to clean the deposits

http://www.r3vlimited.com/board/showthread.php?t=1...

Taken straight from Google, not advising anything at all.

[Ozzie Osmond]

Merc discs do love to rust. Should clean off easily in normal use so long as the car's not left standing too long. Cars do like to be used - especially Mercs.