I once bought an E420 that had a hitch installed - believe it was a Drawtite, had a 2500 pound capacity. It did require some drilling in the beams that run on the side of the trunk. Hitches can be found with an internet search fairly easily. Don't think MB ever posted a towing capacity for the car - they seem to try to discourage such things. I would make sure the transmission was in top shape and recently serviced.