Good morning mates,
Pardon me my ignorance, but the 3-4 OWC seems to be operating in a number of situations which appear to be ok in Nates tranny.
For example if the 3-4 OWC would slip, wouldn't the tranny slip in third while in "D", eh? The torque should go thru the high clutch, forward clutch and the OWC to the rear planetary inside gear.
There would be a third gear only while in "3" - the over running clutch would transmit the torque.
Also would'n there be a second gear while in "2" (torque would be transmitted by the over running clutch)?
Further, if the 3-4 OWC would be slipping there would be a first only in "1".
I'm just looking at the torque flow charts
and as you know, I've never seen a 4EAT fully apart.
There's also a good written description of each gear in each selector position in the manual in chapter 20A Power Train, oparation. Nate, bite the bullet and dig out the manual
!
Tightnening the band adjustment by one turn is an easy try and should do no harm - hard to imagine how that could be thrown off suddenly and cause your problem, though.
Kind regards,
Tapani