Had my car in the shop this week for an oil change and asked the mechanic to check on a brake noise. He ended up replacing all four brake rotors and the pads. He said all the rotor surfaces were rusted, but particularly the rears, to the point that they would not perform adequately if called upon for emergency braking. (I had had no braking problems other than the squeal I reported to him.) What bothers me is that the rotors had lasted so little time. The rears were new only 18 months and about 9000 miles ago. The fronts had been replaced 3 years ago (about 24,000 miles ago). I live in Massachusetts where we can get snow and the roads get salted, the car is outdoors at all times, my commute is only about one mile each way so the car does not get thoroughly warmed up most days, and most days I do not do heavy braking. My mechanic argues that the brakes are rusting rather than wearing out and that more frequent use might actually prolong their lives.
Does this sound reasonable? Do other Northeast owners using MBs as daily drivers find their brake rotors rusting so fast? Of course, I also wonder if my mechanic is being overly cautious (or dare I say it, overly greedy?).

__________________
DavidB29
1992 300E with ASR
35 years of Diesels until now!