I was on the highway last night and my 2500 4X4 smoothly shifted from O/D to third and through a CEL for code P0753. The tranny will not shift into O/D and it feels sluggish from a stop which makes me think the tranny is in limp mode. The Autozone guy says it is a transmission solenoid and suggested I try the transmission kickdown solenoid. Can anyone confirm this or have any suggestions?

 

sounds like a filter or pickup problem

 

After letting it sit, does it go back in to OD? did the OD light come on when it kicked down?

 

After letting it sit overnight it still will not shift into O/D. The O/D overide light did not come on, only the CEL.

 

It is designed when a cel is set not to allow o/d to work until you determine what is wrong with it. That code is for the trans 3-4 shift solenoid/trans relay circuit. Could be just poor electrical connections or the solenoid has failed.

 

It is now also throwing a P0748 code for the pressure switch solenoid. I find it hard to believe both these solenoids went at the same time, what else could be throwing these codes?

I cleared them and they came back instantly.

 

Now that I can reply to my thread again...

I still have not resolved this issue. How difficult is it to get to the solenoids? Where is the 12v feed line to them?

 

On a 2500 Ram only
there is a ATF temperature sensor thermistor
that if malfunctioning
will not allow the auto transmission
to shift into Overdrive
because the false signal
makes the PCM computer think
the ATF is too cold or too hot

 

Hank, where is this temp sensor located?

 

It's on the driver side of the trans in the cooling(return line).http://www.rm-indy.com/wavefiles/2001ramsrvcmanual.zip