Harsh shifting only when warm

[GeorgeK]

my 300TE-4Matic shifts perfectly smooth when cold and part warm.
Now that is gets unusually warm (above 35°c), the shifting gets progressively more harsh as air (and gearbox) temperature increases.
I checked the vacuum lines and modulator, both are fine. I turned the modulator 2 clicks with no result. Oil has 15K miles in the box. Level seems OK (very hard to check, the level is more of a streak than a nice level on the dipstick).

I am about positive that the oil is he culprit, not tolerating the higher heat.

Anyone agrees/disagrees?

[MiguelXJ]

Originally Posted by GeorgeK

my 300TE-4Matic shifts perfectly smooth when cold and part warm.
Now that is gets unusually warm (above 35°c), the shifting gets progressively more harsh as air (and gearbox) temperature increases.
I checked the vacuum lines and modulator, both are fine. I turned the modulator 2 clicks with no result. Oil has 15K miles in the box. Level seems OK (very hard to check, the level is more of a streak than a nice level on the dipstick).

I am about positive that the oil is he culprit, not tolerating the higher heat.

Anyone agrees/disagrees?

How are you checking the level?

[GeorgeK]

Engine warn, running in neutral, on a flat surface after idling a few minutes. Markers on the stick oriented to the back of the car.

[zviratko]

I just had exactly the same problem including being unable to read from the dipstick... But I'm getting slipping 2nd->3rd at random, or harsh shifting at random.... Oil has 2000 kms on it - maybe something got flushed out...

[zviratko]

GeorgeK: you should read the level after either a ride or after shifting to all posititions a few times... PRNDNRNDNRND...

[MiguelXJ]

Originally Posted by GeorgeK

Engine warn, running in neutral, on a flat surface after idling a few minutes. Markers on the stick oriented to the back of the car.

Gear lever should be in Park and engine tempo should be normal operating temp (aka 80-85ºC)

Check it that way and let us know.

[GeorgeK]

I will have the oil changed on monday, so we'll see if it solves things.

[GeorgeK]

I will change the oil on Monday, we'll see if it sloves the problem.

[GeorgeK]

Update:
We changed the oil and filter in the gearbox yesterday evening. The filter element was partly torn from its cartridge and partly sucked into he gearbox, thereby impeding flow out of the filter.

We got 4 liters out of the box and could put only 4 liters in, even thought the manual says 6.2 liters. It registers full on the dipstick, that now works as it should.

Is it all the trouble there was ? I don't know, but it is reassuring that something was not right.

[augapfel]

To remove the most old fluid you have to drain the torque converter. There's a removable plug on the back side of the converter that you unscrew and fluid gushes out. A lot!
Have you made any progress on your cam/rockers problem?