Nothing, the car is in excellent condition.
I have only had the car for a couple of months, but I have concluded it is one of the best build vehicles offered in the market today.
Sell it soon or you will be in for a real surprise. Take a look at all of the other comments for this make and model to see what is in your future. By this time next year, your opinion will change.
One of the best built vehicles on the market? Good grief what are you comparing it against? :-) Granted later year models have improved their overall quality, but the ML still lags way behind other premium vehicles in this price range. Give yours a few more months and you'll soon discover what I mean...