Engine/Transmission (1994 - 1998) Transmission not shifting in overdrive in cold weather

[cclemons]

I have a 96 2500 that doesn't want to shift into overdrive when the weather is mid 50's or below. Anyone have any ideas?

 

[FourBarR]

There is a thermister sensor which prevents shift into o/d when temperure is below a set point. Dont remember the temperature its set at ,and dont have my manual handy. Someone may come on with the info.

 

[cerberusiam]

IIRC, its pretty low like around 20-30 degrees or so.



Any other symptoms at this time? Do you have an RH or RE trans? The gov solenoid on the RE's can have en effect on OD sometimes.

 

[Missouri Mule]

From 96 service manual; 47re



"The PCM prevents engagement of the convertor clutch and the over drive clutch, when the fluid tempature is below aproximateley 10 degrees C (50 degrees F). "



Thermistor normal resistance value at room tempature is 1000 ohms.