'87 300d Trans not shifting right - PeachParts Mercedes-Benz Forum

jfikentscher · #1 09-21-2004, 04:31 PM

Thought I should start a new thread. Well the '87 won't shift right. At startup it will go in 1'st gear only,. If I rev it up to about 25, shift to neutral and shift again into drive, second gear will engage. but no higher. reverse works, Occasionally it will slip out of first.

Drained some fluid and put Trans-X in. Idled and shifted through the gears from P to D2 but this has not helped yet. Just took the car out for about 5 miles and still the same.

I'm hoping that an overnight soak with the Trans-X will work but i'm not getting a warm feeling about it.

Should I keep driving locally no higher than 25mph? Should I take it to a trans shop? The trans was serviced before I bought it by a shop about a mile from here, and has worked flawlessly until now, however i'm sure that any shop will want to sell me more work than it needs.

Any suggestions will be greatly appreciated.

Thanks

Joe.

sixto · #2 09-21-2004, 05:36 PM

Check the kickdown switch under the accelerator pedal. Probably stuck. Disconnect and test.

Sixto
95 S420
87 300SDL

jfikentscher · #3 09-22-2004, 08:24 AM

The kickdown switch has been disconnected for a couple of years. I checked it anyway to see if the plug somehow re-connected itself. No that's not the problem.

Thanks,

Joe

jfikentscher · #4 09-22-2004, 08:36 AM

Took a ride to get the morning papers (less than 1 mile), shifted fine. left it running bought the papers same problems on the way home. shifts into second but no more.

Thought I had it licked.

Joe

jfikentscher · #5 09-22-2004, 01:44 PM

Took it to the trans shop that worked on it 4 years ago. test drove it. Started by saying internal problems. Ended with possibly the vacuum modulator. Advice here??? Please???

Thanks,

Joe

leathermang · #6 09-22-2004, 02:30 PM

Doesn't the vacuum modulator simply screw into the side of the transmission ?If so might be worth a shot at putting it on yourself...
but I would keep doing the driveway shifting through the gears with it running a little each day.... if an orifice has some flow through it the varnish can dissolve pretty fast.. but if it was completely clogged then it will take longer..
There is a moderator on this site ... Steve Brotherton... that has a transmission info site that is great.... you will need that info if you put the new modulator on ....