My girlfriend took hat C350 to the dealer for standard maintenance. The dealer suggested she use the “express” team since her maintenance was standard based upon time/mileage notifications. I’ve never used this team on my current or former cars (e320/ML320/Gl320/Gl350) When she went to pick up her car, as she drove off she felt it was a little sluggish. As she drove down the highway it became more sluggish and started back-firing and black and grey smoke was coming out of the tailpipes. She took the first exit off the highway and was able to pull off into a parking lot about 1/4 later. The dealer towed the car to the shop (when their wrecker svc showed up, he was lazy and told me to start it and back it up (that didn’t happen lol). When they pushed the car onto the lift (we were watching from the service area) the first thing they did was check the oil and we saw them drain it. My thought was they were going to check to see if there was any thing metallic in the oil. Today, the dealer called her back and told her that they added 2 too many quarts of oil.

Obviously my concern is that the additional 2 quarts may have done some lasting damage to various parts of the engine. Not being an expert I thought I’d reach out to this fabulous forum to see if I could grab any ideas as to what I should be discussing with the dealer, Mercedes regional, or even Mercedes corporate. One of my concerns is damage to the engine (foaming, pressure, etc) as well, since this is now in the record of the car, when and if she sells it, this might be an issue. Any thoughts out there? Thanks and please have a safe and happy Memorial Day Weekend.