Whats the condition of the ATF??? Clean???

When was it and the filter last changed (guess you may not know that - but if it is clean it should be OK)??

What is the level of the ATF (when warm)???

May be as simple as an adjustment - I had my trans rebuilt and have had to have it adjusted a couple of times due to hard shifting or flaring (go too far one way!!).

Start with your fluid checks - which you may have already done.

Cheers

__________________
1988 W126 420 SE

beware of fundamentalists!