Hello,
I seem to really need some advise here, if anybody can.
The Problem: on my 1988 740 turbo wagon with M46 4-speed manual transmission, after prolonged freeway drive overdrive does not disengage. I push the O/D button, light goes out, but transmission continues running on O/D on ANY of four gears now. When the car slows down for a while, or stops, it starts going away, but not before some serious jerking with O/D engaging and disengaging erratically.
Fluid is fresh syntetic ATF, two little seals on O/D solenoid are now brand new. Brand new O/D relay kind of seemed to fix it for half a day, but then not. I did not try to clean screens yet.
The problem seems to get worse in cold weather (cold here is around 40 - 50 F) - it was happening a bit last winter, got lost in summer, and now is back full force. Also, when O/D is disengaged, it seems to routinely slip on 4th (maybe 3rd too??) - sometimes a lot, but definitely does not slip on 1st and 2nd. Reverse is always fine.
Another weird thing to note, although happend maybe only twice or three times: if the car is driven aggressively on freeway on 3rd and 4th, O/D did not engage at all, even light was not coming ON. It started working again after about couple minutes of driving.
The problem started getting dramatically worse recently. I am afraid O/D may give way at some point because of all that jerking, also get no acceleration with the thing engaged - would appreciate any meaningful advice.
Thank you.