Warped discs - W203 Sport

[merc07]

My C220cdi estate started feeling like a boat a while back. Gently rocking back and forth when steadily coming to a stop with the brakes on.

I changed the discs and pads with genuine parts and it all went away.

Less than 5000 miles later and I can feel it again, if only very slightly.

The car is a sport edition and has drilled discs and Brembo pads.
I hardly even use the brakes !

Any ideas what may be causing this.

Cheers
Adam

 

[jefrs]

Did you clean the calipers and thoroughly bleed the brake system? - Not likely to be that after 5000 miles.

Are the discs actually warped?
If so what is causing it? - Could be geometry.

It is something-else causing uneven braking?
Does it do it when you brake hard?
- Could be dirt in the calipers. -Could be air or water in the brake line.

A thorough inspection probably worthwhile.

 

[merc07]

I didn't strip the calipers or bleed the brakes, fluid was recently changed.

Changing the discs and pads last time completely got rid of the boat sensation, yes it must have been them. The pads were all worn evenly.

If I drive along side a wall / buildings with the window down, I can here a noise as if the pad touches the disc on every rotation, like I have a nail in the tyre.

If I brake hard I can't feel it but then I don't think you would !

Adam

 

[Paddcomp]

I have the same car and mine is doing a similar thing, possible worn discs. I've done 25K on them, mostly short journeys.

I'd be interested in how you solve the problem, and if it's disc related.

 

[BlackC55]

You will have a build up of corrosion on the hubs (where the discs mounts on to). You will probably need new hubs.

Check the sliders on the caliper carrier are free too.

 

[merc07]

You will have a build up of corrosion on the hubs (where the discs mounts on to). You will probably need new hubs.

Check the sliders on the caliper carrier are free too.

There also seems to be a feint 'droning' noise from the front right as well. Maybe the left also, wouldn't know but I can definatley hear something on the right.

Are the hubs much of a job / cost ?

Cheers
Adam

 

[BlackC55]

Not expensive or difficult to do. Just make sure the bearing is done up properly as it is a taper type.

 

[stevesey]

You will have a build up of corrosion on the hubs (where the discs mounts on to). You will probably need new hubs.

Had this once - removed disks a second time, noted slight corrosion on the mating surfaces (hub mainly as disk was new - but surface was "stained" but the corrosion) - cleaned up with wire brush/wet and dry. Did the trick.

 

[merc07]

Had this once - removed disks a second time, noted slight corrosion on the mating surfaces (hub mainly as disk was new - but surface was "stained" but the corrosion) - cleaned up with wire brush/wet and dry. Did the trick.

Thanks, I'll give that a go 1st,

 

[BlackC55]

Cleaning them works only if new discs are fitted. Generally as soon as the warping has started the disc will be U/S.

I also use a small chisel to remove the larger lumps. Wear goggles too.

 

[merc07]

Cleaning them works only if new discs are fitted. Generally as soon as the warping has started the disc will be U/S.

I also use a small chisel to remove the larger lumps. Wear goggles too.

Will it stop them getting worse or do I have to buy another set from you after just 5000 miles !

Maybe I could get them skimmed, or is that just for wear, do they still do it ?

ADam

 

[BlackC55]

It is not the disc face that gets warped it is where it mounts on the hub. Clean them and see how it goes.

 

[merc07]

Cleaned up the hub face and discs over the w/e
There was quite alot of crap on them.

Do the discs just warp if you put new ones on without cleaning the hubs or will new discs on new hubs warp over time due to the build up of crap behind them.

In other words do they need regular cleaning or just when they are changed.

Cheers
Adam