1990 300E Hard shift into passing gear

[tysmith747]

This problem is metioned in my other post for reference to another problem. I wanted to start it's own topic here.

The car is shifting very hard from 4th into 3rd on the highway. 55-65mph. It shifts smooth through all other gears. Also it shifts smooth in manual from 4th to 3rd. Only in (D) am I having this problem. There also seems to be a little bit of a "whine" at low speeds. Normal?

Thanks,

Ty

[Jayare]

Ty,

Help yourself and the rest of us out here by completing your profile. How long have you had the car? Mile on it? When were all the fluids, filters changed? Basic tune up done, wires, plugs, cap, rotor? With any recently aquired car, you need to establish a base line for maintenance. Many of the questions you have in your other post can be resolved by first taking these needed steps.

Let us know, welcome to the forum and good luck,


Jayare

[tysmith747]

Sorry, profile updated. It was my mother-in-laws car, I have no records of the service on the car. She had it about 3 years. It has 119k miles on it. I've had the car two months now, but haven't driven that much. I've been replacing the left front fender and bumper due to a fender bender she had in it.

Ty

[Real1shepherd]

Originally Posted by tysmith747

This problem is metioned in my other post for reference to another problem. I wanted to start it's own topic here.

The car is shifting very hard from 4th into 3rd on the highway. 55-65mph. It shifts smooth through all other gears. Also it shifts smooth in manual from 4th to 3rd. Only in (D) am I having this problem. There also seems to be a little bit of a "whine" at low speeds. Normal?

Thanks,

Ty

I would do the usual...take some time and acquaint yourself with what the MB specs are for your tranny. Either find the right spec ATF or consider a synthetic (with the right specs). Either way you go, figure on replacing the fluid in the pan, the gasket and the fluid in the torque converter. Plenty of tutorials on this board with a search.

Most of these trannies do hard shifts as they warm up, and it's normal until the cat(s) get to operating temp. After that they should shift a lot smoother. You could adjust the modulator, but that should be done by the book and not a 'road guess' as some suggest, IMHO.

If after all that you're still having the one hard shift after warm-up...I'd live with it.

Kevin