My 85 500 SEC tranny will not upshift in the drive position. It will
only stay in low gear when placed into the drive position. The
only positions the tranny works in are drive, neutral, park and
reverse.

Could someone please tell me what other model benzs use the
same tranny. I was told the tranny I have is a W4a70 model
722.311. I was also told the 84-85 500 SEC/SEL are the same
as well 86-91 420 SEL's use the same tranny and are
interchangable. Could someone please set the record straight.

I'm looking for a used tranny. I dont think I'm really gonna keep
this car long because I've got too many restoration projects I
need to complete.

Thanks!

Is your car Euro or american? my Euro 86 500 SE has a 722 311 transmission (I just had it out to reseal it) And it has a Euro 116 420 engine instead of the original 117 500 engine..........
William Rogers........

My 500 SEC is an American model