On the 2000 2500, with a DTT style tranny. Was running on the interstate and making good time, with the wife driving following me, the "OD off"" lite came on and RPM's increased accordingly. At that time she could not do anything to get it to go back into overdrive. We took the next exit and I could not visually see anytimg out of the ordinary. the tranny pan was not at all warm by feel. When we took off again all seemed to be ok. She was pulling an enclosed trailer ( 18 foot ) with not much weight in it (PIG cooker maybee 750# total ). Any thoughts? Thanks

 

OK brain dead. I thought I put this in the 24 valve section.......

 

the gov. solanoid in the valve body controls the overdrive signal....it what tells the tranny computer to shift..... the speed sensor also effects it but it wont shift out of first if that the problem.....if your having tranny probs ask me...im really good at these trannys.....after rebuilding my own 3 times for different stuff shattering inside them you tend to learn the ins and outs on them.... plus i have the book on these trannys