My 1993 Dodge 5.9 Diesel is having shifting problems , while driving the truck it shifts from overdrive to drive and at times it won`t shift back in to overdrive.
I have had it at several transmission shops, one shop said it was the cable that runs from the throttle to the transmission. I replaced it and it didn't help . The transmission shop said , whether it is electrical or cable or etc.

Sorry if this is posted in the wrong area of the forums first time user

 

This could be many issues but if it's like mine it's electrical. Once you have your TPS checked, trace your OD power wire from there(orange with black strip) and follow it to the tranny and to the solenoids that are on the drivers inner fender. On those 4 solenoids there should also be 4 pop off connectors. Take them off, clean them and di-electric grease them. This seemingly worked for me because everytime I hit a bump it would kick out. As far as the electrical part of the tranny goes... it could also be a few things but not likely internally. Just fool around with things and plug the grease to whatever you come across.

 

The O/D is electronically controlled. You replace the cable but you need to make sure its adjusted correctly. Once this is adjusted and it still drops out like that you need to check the TPS and either adjust it correctly or possibly replace it. Most likely its an electronic problem, but not internally.

I would, as I have done this on my in-laws truck, just hook a toggle switch to over ride the computer control and anytime you turn the switch on it will lock in the O/D. This is the easiest and simplest thing to do. I am also going to work on building a relay setup that will drop out the O/D if you hit the brakes. There is a schematic floating around this place somewhere, it says its for a 2nd gen but it'll work for our application fine.

 

Sounds like a bad TPS.
That is what mine did when the TPS went bad.
It only takes a couple of minutes to change, but may take all week to pay for it. Mine was just under $200 and a dealer only item.

 

I just losen the TPS and reset it, sometimes I just tap it that seems to work. I will be needing to replace my TPS soon I think.

 

Maybe this`ll help
https://www.dieseltruckresource.com/...ad.php?t=74673

 

Nice find and fix need a trany service soon will look at that. Thanks.