I did my own oil changes after Starmark warranty ran out. Personally, if I had a $55k car under warranty, I wouldn't be worried about the extra $40 or so savings every 5-10k, I'd be worried IF something happens to the motor, MBUSA is going to kick you in the face. On that car, I'd take it to the dealer and keep full records until the warranty is gone.

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former: 83 300D, 97 C230, 93 400E

current: 08 C300 Luxury , 92 500SL