Truck refuses to shift out of first when driving. Even manually putting it into second gear it just stays in first. Bought It for my first truck and the guy told me it was a solenoid problem. Trusted him till I found out it was a hydraulic trans. Any advice on what might be wrong? And how to fix it?

 

Check and see if the TV cable is bound up. If it works the way it is supposed to, it's rebuild time.

 

It's a Hail Mary but you can try a can of Seafoam Trans Tune. View it like a lottery ticket.....ie you're not really mad if you don't win

 

If the transmission is a 46RH it could be a couple of problems. One it could be the governor body and valves or the Valve body itself. If the transmission is a 46RE then it the valve body..