I have had a my 1999 SL500 for 9 years. The brakes have always squeaked when I lightly apply them while backing up slowly. I changed out brake pads with MB brand brakes from the dealer...no help. Recently they are incessantly squeaking when I lightly apply the brakes in the forward direction at very slow speeds.. VERY EMBARRASSING when I pull up at a nice restaurant! My mechanic suggested I hit the rotor with a car washer. No help. I have confirmed they are the front because I slowly applied the emergency brake and no squeal. Also car is 100% garage kept and covered. Only driven 3-4K miles per year..PLEASE HELP!! Thanks in advance..
Fill out your profile. Your location would have helped you more. Am I assuming you are in the States?
Anyway, in case if you are, you can order the rotors from your local MB dealers or parts.com (cheaper but come with risks to some people). The pads could be ordered from tirerack or any websites that sell Euro Akebono.
ROTOR SA FRONT 129 421 23 12
ROTOR SA REAR 129 423 05 12
These rotors are cross-drilled.
My car started to have what you have described since around 16K miles on the odometer. I had to drive like that to around 45K miles with all the embarrassment. Replaced the stuff mentioned above and life has been good since (the car now sits at 91K miles)