I have a 1999 ram 1500 4x4 with a 5.2 magnum and a 46re. I nuked the trans I bought with the truck but it was in rough condition when I bought the truck. I put a used trans in. When the trans is shifting right, it’s super smooth, not jumping or lunging even when pedal to the floor. Shifts smoother than my Honda did. But here’s where it gets very strange. When I first put the trans in, it would shift fine all the way through the 4 gears and reverse, but there would be a “trans temp” and “O/D off” light when I first start the truck. So obviously the trans isn’t hot. Truck shifts perfectly even when these lights were on, there would be a lot of slip in the torque converter but it would drive which is what matters. Then I started driving it more and now the lights come on about a minute after start up, even if the truck hasn’t moved and I’m completely locked into first gear with a very responsive torque converter. Then the lights shut off and about 10-20 minutes later I will get the other gears back as if nothing was wrong to begin with. I have a check engine light with codes “P0740, P1763, and P1762” the first one is a lockup issue and the other two are high and low voltage on the pressure switch. I have a new pressure switch and governer as well as a filter and gasket to try and fix it. But I wanted to know if anyone thought it might be something else.

 

Sounds like an electronics mismatch. What year vehicle did the trans come out of?

 

I think it’s out of a 98, but the guy I bought it from wasn’t certain if it was a 98 or 99. My truck was built in 98 though

 

Hhhhmmm.... That shouldn't be a problem then.

I think changing out the governor pressure sensor, and solenoid, wouldn't be a bad place to start..... (new filter and some fluid at the same time.....) While you are in there, make sure the wiring harness hasn't been damaged. Also, be sure and get the right parts for your year truck. Things changed for the 2000 model year inside the trans....

 

thanks for the info on parts, I didn’t know they changed. I’m pretty sure they’re the right parts. I’ll do an inspection on the harness as well.

 

I would start off replacing the solenoids with part number which is a Mopar number. 52118500 that comes with the wires and solenoid for a 1999 ram truck with a 46RE trans.