So, my father is on his way down to Virginia from Boston. He gets to about Danbury, CT. and says that his car won't shift into 4th gear. He has a 1991 Mercedes-Benz 300SE. Obviously, this is some kind of transmission problem, the question is, what, and how bad. This car is a 4 speed automatic, with 130,000+ miles. He rented a car, and contunied on his way. He left his car at the local Mercedes dealer there, but would much perfere to have it worked on here in the Boston area. On Monday, he'll bring the rental back to Danbury, and he plans to attempt to "limp" the car home from there. My questions are as follows:

1. Is limping home wise, or can he further damage the tranmission or other parts of the car?

2. What might be the cause of this problem, and does it require a new transmisson?

3. If he does need a new transmission, where can he get one that's stand alone that he can have shipped to his local mechanic?

4. What might a new, or rebuilt transmission cost?

5. Could this be anything else besides a transmission problem?

Please let me know what you all think. Any information would be very helpful. Thanks!

 

It could be the gearshift position switch, the shift linkage or the 3-4 shift solenoid, or a few other things. I assume it's not low on fluid. I would suppose it's an all hydraulic trans with an electric lockup clutch.
If it is otherwise shifting OK (not slow or delayed) it might be OK to drive. If it's shifting slowly it might have a weak pump and driving it might kill it off.

I would check to see if the linkage is OK, if it is loose or has slipped he might get stuck in another gear (or in Park.) However moving the selector around might find 4th gear too.

I think this trans also has a throttle cable conenction (kickdown cable.) If that is too tight it might never shift to 4th as the trans thinks you are applying a lot of throttle. The kickdown cable shoud not be too tight, or too loose.

You could ask the 928 guys or perhaps one of the Benz forums for better info.

Good luck,
-Joel.