Traveling PA - Our 2014 Sprinter (6 cyl) only has about 15,000 miles on it and hasn't needed anything more than routine service at the local Mercedes dealership.
However, I was less than impressed with the service department there - the Dodge dealership that worked on our old van was far more professional and far less expensive than the Mercedes people. Among several other strange things, they didn't want to top up the DEF fluid, which is about as difficult as adding windshield washer fluid. They would do it but they would have charged me $130!