Why do Inside and Outside Rear Brake Pads Wear Differently
 

On changing my W126 rear brake pads I noticed a significant wear difference ... the outside pads were worn out and the insides looked like they could go another 100K. It was the same on both sides ...

There is likely a good reason for the difference in wear - I suspect it may not even be related to a problem?

The brake calipers must not be operating properly!!

Is it ok for the front wheels (not tires) to be warm after light braking on a 4 mile run? Just curious because the rear wheels were totally cool...

Tank,
 

I think is like 90% of your braking job is done by the front brakes. Therefore, the difference in temperature.:cool:

MBDoc,

That's what I thought, too ... piston appears to be moving smoothly (checked it) ... isn't it odd that BOTH rears would wear the same ... maybe any apportioning issue at the master cylinder?

<<< piston appears to be moving smoothly (checked it)>>>

Do you mean pistons ??

I experienced the same thing to a lesser degree when I changed the rear brake pads on my C280. Outer pads were 2 mm thick and inner pads were 3 mm thick. Pistons move freely are not sticking. It was the same exact wear pattern on both wheels, but for some reason the inner pads were worn just a touch less.

If both pistons are moving freely, it just may be that there is a slight amount of air/crud at the bleeder port and the inside piston is the
last in line , therefore being the last to move...????
Just conjector... but I would bleed anyway....

Yeah ... meant pistons ... one for each side of the rotor on the rears ...

Can buy the problem alternatives ... just seems odd that it would be on BOTH rear brakes with no difference ...

Thanks.

George,

I agree it's pretty coincidental that you've encountered this phenomenon on both rear brakes; however, there's no question that the pistons that contacted the greater-worn pads are hanging up in their bores, and need to be rebuilt.