My 2001 2500 4x4 ctd with auto is having problems when I come to a complete stop and try to take off again the transmission stays in o.d or third gear if you throttle on it pretty hard it will downshift or you can manualy pull it down into 1st and it will downshift?????.Any help would be greatly appreciated.Thanks!!!

 

How many miles? How much horsepower? Possibly the VB isn't making the downshift because particulates from friction surfaces are clogging the orifices. Does your OD lockup slip or shudder? That produces particulates. Changing fluid does not clean the orifices. Mine would not readily make the 2 to 1 downshift and the lockup would slip with increasing frequency so I bought ATS.

 

The condition you describe is called 'limp mode', Most likely it is the pressure transducer and or solenoid.
It tells the computer that the internal pressures are out of spec.

i would drop the pan to inspect it for debris and go ahead and change out the to items listed above.
solenoid# is 04617210, Don't know the other.

 

Thanks for the responses. The truck has 80000 miles on it and the transmission was rebuilt at about 30000 miles after an accident.The engine and drivetrain are both stock.thanks again.