1988 300SE Slow Shifting

[RC2007]

My car seems to be taking forever to shift. It shifts smoothly but the duration of the shifts seem way too long and it is killing acceleration. Any suggestions??? Thanks

[Lead]

check/refresh your tranny oil...

[RC2007]

New Fluids and Filter already.

[S-Class Guru]

Check some easy, obvious things first:
1. As the guys said, drop the pan and change the filter and fluid.
Drain the converter also.
Look for little pieces of friction plate in the pan or in the filter, they will look kinda like big East Texas ticks - Ha. If you see any of these little brown pieces, time for some serious work.
2. Check the Bowden cable that attaches to the throttle linkage. Pop the ball socket off the cable end and check the adjustment. It should be adjusted so that the cable pulls out easily, then hits a harder resistance as the slack is all out. At this point it should just pop on the ball with no slack or no resistance.
Turn ther white nut to lengthen/shorten it accordingly.
3. Check the vacuum line to the modulator. It runs from the back of the intake manifold down the left side of the tranny.

DG

[Mike Murrell]

I'm not a transmission expert, but my '91 300-SEL started to act a bit as you describe some years ago.

A skilled MB tech replaced and adjusted the vacuum modulator mentioned above. That part is relatively cheap as auto parts go these days.

Replacing would not likely be all that hard and I do not think adjusting would be either if you have the time. Back then, I didn't have much of that.

There have been many posts on this forum regarding the vacuum modulator. If you decide to tackle this, use the SEARCH facility here.