I have just attempted first time,to replace new front disk pads on 89'560SL. The first pad I removed (A) was worn down to almost touching the sensor. Now here's the odd thing....the inside pad (B) was only 40% worn down?? when I attempted to insert a new pad into (A) I could not get it into place....the pistons would not withdraw enough (no how). The inside... (B) was no problem. So what I had to do was place the 40% worn one back into (A) and the new pad into (B) Could anyone explain why they did not wear down evenly in the first place ? and what could be the problem with the piston not fully withdrawing?
I checked all the other brakes and the pads were all showing about 40 % worn.
So I just had the one worn pad. Your thoughts or experiences would be greatly appreciated.

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Dalai Lama.

probably your rotors (discs) are uneven. Did you ever have them grinded before?

it quite possibly is caused by a stiff piston seal not allowing the 'worn' pad to retract. I suggest you rebuild at least the ueven wear caliper.

You need to replace the calipers with rebuilt units + replace all flex hoses + flush the brake fluid.

Brake:
http://www.peachparts.com/shopforum/showthread.php?t=142411



Have a great day.

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I have only had the car 1 year so do not know if the rotor was ever ground.
To 'rebuild' a rotor, can that be done by myself or is it a professional job?
I will look into all your inputs and proceed accordingly. Thanks again, you've been a great help and much appreciated.

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Read what Arthur Dalton had to say in the following thread B4 forking out $$$ for new Calipers:

http://www.peachparts.com/shopforum/showthread.php?t=123577&highlight=caliper+hose

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Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

read here before that MB rotors are not supposed to be ground, but replaced when they wear beyond specific thickness.

Thanks all.........your info was well inderstood and now will be applied.

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