Tranny goes clunk - When first cold shift 91300E
 

My 300E 190K has developed this "clunk" whe first shifted to reverse every morning. After moving for even a couple of minutes, shifting to reverse makes no noise after that. What is going on??

Keep an eye on this behavior. The possibility exists that you may be seeing the beginning of the 722.321 MB "reverseitis". Check the fluid level, change the fluid and the filter ASAP. Don't forget draining the torque converter. There is a control valve in the valve body called the reverser servo start control valve, or something like that. I had the exact same thing happen to me. It required pulling the valve body and cleaning the valve and it's bore. When it's cold, clearances are tighter. When warm, things open up a bit. Keep us posted..

Thanks for your reply. ATF (Mobil 1 yearly changed) and filter (every other year changed) of tranny changed only a month ago. So is this valve body easily accessed? DIY? Major steps description? Thanks