I've seen several 221's and 216's go through front brake pads in less than 15,000 miles. They were all regularly driven in New York City, if that matters. The lip on the rotor is normal, as long as the rotor thickness is within spec (30mm MIN. for an S550), so they shouldn't need to be replaced.

I've gone through front brake pads on my 560SEL's and 560SEC in 11,000 miles. At the end of the 11,000 miles I had a very pronounced ridge on my rotors too. However they were still within specifications until the next 11,000miles when they were out. It depends on driving and subsequent braking style that affects brake/rotor wear. I've never gotten less than 11,000 miles or more than 20,000 miles on any set of front brake pads.


'87 300SDL 254,000
'94 SL500 42,000

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jcciem
'94 SL5000 60,000
'91 350SDL 545,000
'91 350SD 197,000
'00 E55 AMG 77,000