With Mercedes Benz transmissions make sure that the fluid level is correct, too much fluid can be a problem just like not enough fluid. With the car running (cold) the fluid level should be 10mm below bottom mark. On a hot trans(driven at least 10 mi) the level should be between the marks. Never allow the fluid to get above the top mark.
MERCEDES BENZ MASTER GUILD TECHNICIAN
ASE MASTER TECHNICIAN
27 YEARS DEALER M.B. TECH
190E 2.3 ITS RACECAR