Hello,
Jeffrey, is the dealer Leith Mercedes? I have had the same thing happen to me with the 2000 ML320 that they supplied. The service advisors there are very clever in the sense that they will take care of any warranty work without even raising an eyebrow, the HB, brake master cylinder and some small clip was replaced hassle free on that car but then they hammered us for a rear brake pad change and related stuff for $700.
I was not in Raleigh at the time and unable to do the work myself and Leith convinced my niece that the car needed new pads *immediately*, but when I asked if the wear indicator lite was blinking, she said *no*, then upon measuring the old pads, there was still 5mm friction material left, Leith's reasoning was that the pads would not have run until the next time the FSS lit up, which was set to 12 months on that car.
Well, they are there to make money, after all. No matter what the level of service or friendliness I find at any dealership, I still prefer to do my own repairs as far as possible or let a competent indie work on my car while I breath down his/her throat.

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Nachi11744