Years ago, I took my old 200D in to the dealer for a valve adjustment. When they called to tell me it was ready, they commented that they had also tightened the fanbelt amd asked if that was OK. I told them sure, it was OK that they tightened the fanbelt. When I picked the car up, I found that there was a $50 charge for tightening the fanbelt. The service advisor explained that this was because they had to precisely tighten it to MB specifications. I drove the car for a couple days and noticed it was making an intermittant clunking noise which had not been there previously. Upon opening the hood, I found a 2 1/2 foot crowbar dangling from the air cleaner nozzle. This was when I decided I had better learn to do my own routine maintenance. I still have the crowbar to this day. The dealer went out of business a year or so later.
2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg
And remember folks, Only You Can Prevent Hilliary.