Go to the following: http://www.remcotowing.com/ They have a transmission lubrication system specially for the MLs. It consists of a 12 volt pump, control valve and pressure sensor. It is powered from the motor home 12 volt power and there is a warning buzzer and light in the motor home that monitors the pressure in the transmission line. This is a very well respected company in the RV community. I have towed my 2003 ML 500 for about 10,000 miles with no problems. They will recommend a local welding shop for installation. Mercedes should go after this market since most of them end up towing Jeep Grand Cs. and I am sure many would rather have a Mercedes. Anyone doing this should make sure, that since they have to drain the transmission fluid, that it is refilled with the Mercedes transmission fluid and that the right amount of new fluid is used. I would recommend that it be checked at the dealer and a new sealed device be installed on the filler cap.