mikefili

I have a C300 with 1300 miles. I have noticed that the Right Rear wheel has much more brake dust than any other wheels, much more even then the fronts, although all the wheels have in my opinon too much dust entirely. I have had nothing but german cars my whole life, so I do know that they have more dust than most. The dealer agrees that the right rear is much worse that the other 3 wheels and explains it that the car because of it's power is applying the brake to prevent wheel spin, total B.S. It is amazing what absurd things the SA will say to us the customer, almost as if there is a prize for the most absurd statement. I also have an SL 500 that seems to not make any brake dust at all. Anyone having the same problem with the right rear wheel?

acr2001

The brake dust has to do with the brake pads used, and its normal to get a ton of it with the stock pads.
If you want to greatly reduce brake dust you should replace the pads with low dust pads.

As far as the right rear making more dust than the left rear, this suggests (someone tell me if I'm wrong) that your brakes are not working properly. The 2 rears should have even amounts of brake dust, as should the 2 fronts, because brake force should be (usually) getting applied evenly between the two.

Obviously if one wheel is slipping then the brake dust / force is not going to be even, but like you said, that is BS because that wheel would have to be constantly slipping while the other one does not!

I suggest you have someone look at your rear brakes and see if they need to be adjusted.

RLE

<<I have a C300 with 1300 miles. I have noticed that the Right Rear wheel has much more brake dust than any other wheels, much more even then the fronts, although all the wheels have in my opinon too much dust entirely. I have had nothing but german cars my whole life, so I do know that they have more dust than most. The dealer agrees that the right rear is much worse that the other 3 wheels and explains it that the car because of it's power is applying the brake to prevent wheel spin, total B.S. It is amazing what absurd things the SA will say to us the customer, almost as if there is a prize for the most absurd statement.>>

I wonder if you know how ESP works? This explains the service writer's statement, to me at least, but I think he's stretching a bit. It is true that when the RR wheel breaks traction, the brake will be applied to that wheel to enable it to regain traction again.

BUT, when that happens, the bright yellow ESP warning will light up in the speedo. If you haven't seen that, then it's not happening.

I will say, though, that at 3300 miles on my C300, that the brake dust on the wheels, particularly the rear, has diminished considerably.

Give it a while.

Oh Cool

That's good news to hear.

Lakerz4sho

yes, i notice a lot less brake dust after the break-in period. i'm at ~4k miles now.

kimyoung_k

My C300 4Matic has lots of brake dust built up on rear wheels and very few on front wheels unlikely my 96 C220 which most brake dust built was happend on front wheels.

I read from somewhere that W204 purposely applies brake more to rear wheels to reduce the nose down when stopping. That is why W204 has dirtier rear wheels than front which is uncommon for other cars. I don't know about why one of the rear wheel get worse than the other though.

oblu

Your SA might be right on this one. My right rear is dustier than the left rear, and I know I'm always dipping into the ESP.

JimPap

If you're driving fairly moderately (not too aggressively), I'd think that you've got air in the left rear break line causing the right rear to do most the stopping.

KHill

I'm also having more right rear brake dust on my C. I haven't noticed the ESP light coming on, so I don't think it's the ESP. My R500 didn't have this problem and I was always into the ESP on the R. I will say something to the dealer when it goes in for my LoJack install and 1000 mile service.

jjgoat

Look at your rotors. Only the front ones are slotted (I think that is the term, or perhaps drilled). The back ones don't have those same holes in them. Those holes are what allows the front brakes to stay practically dust free.

451/443=EW

Sorry but no. those drill front disc are for quicker cooling of the disc to allow for better stoping power not to keep your rims clean. The fronts should always get dirtyier than the rear's cus the fronts are 70% of your stoping power. In this guys case it seems very strange to have the back one get dirty quicker. Just a guess but maybe your rear brakes are still active while your driving? Might not be you leaving them on, it might be something wrong with the rear brakes that they dont disengage?

AkaSigFreak

The brakes are most likely not engaged by accident. The reason for more brake
dust in the rear is the traction control. It limits wheel spin by slightly engaging the brakes to maintain control. And you might notice the passenger side usually has more brake dust than the drivers side.

jjgoat

Hate to correct you but you are only half right. Yes, it does keep them cooler but it also allows for the brake dust to pass through and keep your rims cleaner. I have the same problem with my rears getting dirtier and NO there is nothing wrong with them.