I have rough shifting on my wifes 93 300D 2.5 Turbo. IT changes smoothly at low revs, but when you give it a bit of heavy foot it clunks through the gears - it's a very quick change, and a bit of a jerk. Doesn't feel right to me.

I've checked the tranny fluid level - all good.
The vacuum system had a piece of acorn or something in it that I removed, but that didn't change anything

Any ideas? I'm not up on these cars - I have a 240D that I know very well, but this one has me. I don't even know what the chassis model or engine model is!

Any body got a link to the vacuum system for these cars? I have a haynes manual but it's useless.

If I get this fixed I'll be in big time with the ol' foxy lady. Help me out guys!
Thanks.

It sounds like the vacuum modulator. Just like your 240D has one. There is a vacuum line that runs off and down to your tranny. Unplug it and put a vac pump on it and see if it holds vac. I if not then there is the problem. It's a 45 dollar repair. Just when you take it out, whatch out for the plunger inside. You brake that and good luck getting it out. The Punger part is cheap, just not easy to get out if broken inside.
Later,
Rob

PD,

You have a 124.128 Chassis
with a 602.962 engine
and a 722.4 transmission

As you know , if you "floor" the 240D the shifts will come more quickly and more
firmly. 'Not neck snapping, but definetly more crisply than an american tranny.
So do all the other diesel 'Benz's.

Playing with the vacuum control on the side of the tranny will "loosen or stiffen" your shifts.

There is also the "Bowden" cable which connects the "Throttle" cable to the
transmission.

BOTH must be adjusted to specs for the tranny to shift correctly.

If you follow the vacuum line from the vacuum modulator (on the driver's side of the tranny) up through the engine
compartment ,It will go through a damper [vacuum device in the line] and then to the "Vacuum Amplifier" (on the
driver's side wheel cover)

Thanks Compress and occb - I'm going to have a good look at it this weekend.

I appreciate the info. Good to know what chassis and engine you're looking at!

I don't have a vacuum pump but I have a vacuum gauge so I'll see what's coming out to the tranny. I know what it is supposed to look like on the 240D so I'm sure it should be similar on this one.

P