Our local dealer MB tech who has his own 500E, said the R129 specific transmission oil-filter that has an "acceleration check-valve" is not necessary since the filter is bathed in tranny-fluid.

At over $55/each vs. the $12/each for the standard W126 tranny oil-filter, is it really worth it?

Is he correct? I would think the "Factory" knows best, but who knows.

Why doesn't the C36 or C43 which has the same pan, also use the same "acceleration check-valve" in their trannys?

Both pull just as fast as our 500E's, at least upto 90 MPH.

BTW: what would happen if I installed a R129 "acceleration check-valve" filter into our C36 tranny?

:-) neil
1988 360TE AMG
1993 500E