our trucks are fly by wire..no throttle cable...look at the very top of the go peddle..you will see a switch..un plug it and use some electrical cleaner and try to clean things up...it may not work but worth a try..the switch comes with the go peddle...its 125 bucks....at the top of this page click on FTE guy..he has the best price..I would start there before I worry about Trans just yet..throttle position plays a role in the Trans..this may be your trouble..

 

I can't imagine how a torque converter could set a 3-4 shift error code.

The problem is with your overdrive clutch, or a shift valve. I think you might want to take it to some other shop that will take some time to diagnose what's wrong instead of just replacing the trans.

 

JC, Mark right there would be THE help of which I was speaking......

 

i cleaned the elec conectors on the go pedal. and still nothing. do you guys think that the other codes could have something to do with the o/d problem. Also can some one recomend a good shop to take my tuck to. I am in Houston. i tried going to the dealer cause i thought they were the experts but that was no help.I need a trans shop here local. Some one who can do what Mark stated. i also dont feel i need a trasnsmision because all my other gears work just fine. its just my overdrive. i swear this is driving me crazy!!! My cruise control works my spedo works everything works. What will happen if continue to drive the truck with out overdrive? could the engine get damged too? Could it be my rear diff???

 

I reread your original post. I think the next step would be to take the plastic cover off of the steering column. There are three screws on the bottom of the column.

When it's off carefully inspect the three wires the go into the shifter handle. They are frequently damaged. If the right wire shorts to the metal in the column it will turn off the overdrive and turn on the OD OFF light.

 

Yep, that's what happened to me.

 

i will ispect the shifter again. Thanks for the photo Huck I will carefully look in to that area.Last time i checked i think the area i was looking at was closer to the plug on the lt side of the column.Thanks

 

To take off the housing I would look at f350 (Chris) suggestions on this thread: https://www.ford-trucks.com/forums/8...umn-short.html

 

My original comment was posted before he posted the codes he was getting.
I was just stating what was wrong with mine........it had the same symtoms as his.
Hopefully, he won't need a new trans but I did.

 

I have a '96 F350 turbo diesel. It wont shift into OD, I have changer the shift lever and the OD switch. Still not working, can anyone help?

 

If it is the wiring...Depending on how easy it is to fix or where the "break" is, don't spend too much time on it. One of our other members just replaced his and the shifter with wiring and all cost him $40 at the dealer. 10 minute change out. Sometimes easier to just replace it than to repair it.

Hope it's just the wires.

 

Hi. I replaced both the shift lever and the switch, still nothing. Any more ideas????

 

I had the PO783 code on a recent trip pulling my fifth wheel in Colorado. OD light came on and after my next restart was gone. I removed the code, and it has not come back yet.
I do not beleive that I have any transmission problems.
I did have the broken wire in the shifter a couple of years ago. Wire was broken where it came out of the lever.