My 2001 3500 has developed a new shifting problem. When it is cold it is fine. After driving a while, the 2-3 upshift is stuck. It will run to redline, at about 30 mph. Only way i can get it to upshift is by backing off the throttle, and gently giving it gas again. When it does upshift, sometimes it will suddely downshift back into 2nd again. It usually wont happen if I accelerate real slowly. After it hits 3rd it shifts fine through the rest of the gears.

The trans was rebuilt about 15,000 miles ago at 118,000. I had a new heavy duty TC put in also. There are no codes coming up on my scan tool.

 

My truck was having a similar problem and it turned out to be a combination of 2 things. One there is a large electrical plug on the side of the engine under the fuel pump that needed cleaning. This helped for awhile but then similer problem appeared and it was a broken wire going to the trans. Do not know if our trucks are similer in this area or not. Lots of luck with your repair.

 

Classic symtoms for a defective Governor Pressure Solinoid and/or a Transducer (Pressure Sensor).
Best to replace both while you have the pan off!
About $200.00 for the parts and easy replace if you have any mechanical skills.

RJ

 

Thanks for the help guys. Guess i'll drop the pan and swap out those parts.

 

I went through three of them in my truck,
By Chryslers own admission, one in ten fails, evn the new replacement ones.

 

Before throwing $140 dollars to aftermarket parts, try replacing the RPM sensor on left rear of tranny assy. It only bout 20 dollars and cheaper replace than figure if bad/erratic. If you had the Chrysler diagnostic tool you could figure which is bad.