The problem is a bad, out of round Balo rotor - it's got a high spot on the hub portion. Every time the rotor comes around the high spot scrapes the inside edge of the outside brake pad. I can see where it's wearing itself down. I'm going to try to live with - see if it self corrects. If it doesn't I'll try another brand of rotors. Thanks for all the help.

...seeing it's new , you may want to turn it .. if it just has a high spot , you may get away with it.. if not , no big deal as you were going to try another set anyway

I am not a turn rotor guy, but i would try it in this case...
Star sequence when tightening is a must on these....

I may try that - if I can find someone who's reasonable about it. Never tried it before.

Lots of the auto parts stores do them and for cheap..
..at least that will tell you how far out it is and give you smooth brakes in the meantime.. may even last as long as the other side ..
Easy enough to do.

I just bought new pads and rotors and am changing the rotors for the first time (yeah, I know...first time??!!)...

...what do you guys use to clean the rotors prior to install?

and what is the size of that Torx (or Allen) bolt that holds the front calipers in place (93 W124 M104)?

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

Keep in mind that rotor 'warp' is not actually warping at all. It's caused by hots spots on the rotor. There is an excellent article on Stop Tech's web site about rotor 'warping' and proper bedding of new pads. If you have a heavy brake foot in stop and go traffic that can really tear things up as you are constantly burning hot spots into the rotors.

for normal driving there should be absoltely zero need to go with slotted or drilled rotors for this car. If you want to do something then I suggest a mild slotting over drilled. Drilling weakens the rotor.

calipers are sticking it could heat up the rotors and warp them perhaps.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

that too, how old a car are we talking about? maybe it's time to change the rubber lines going between the chassis and the caliper. they could be causing some caliper hang.