I am the proud owner of a 92 Dodge D350 4x4. I had the transmission rebuilt about 2 years ago and I am still having trouble getting my pickup to shift out of overdrive. Its not a continuos problem just once every blue moon. I talked to a mechanic and he told me to check the speed sensor, but how do i know its bad? Just replace it and see if that makes it better?

 

The speed sensor is localed in the trans case.