Was driving home the other night on the highway, and hit a slow down due to traffic. When it cleared up, and I tried to get back up to speed, the truck wouldn't shift into to 4th gear. It kept running at about 4000 rpm at 65 mph. Got off at the next exit to check transmission fluid, which seemed fine. Turned the truck off and on. When I got back on the highway, the problem went away. Now it's doing the same thing off and on. Usually when I start driving, it shifts fine. If I hit a slow down, it won't seem to get back into 4th. Any ideas of what's going on? Maybe the transmission solenoid and pressure sensor? I already order them both, and will change the atf fluid along with them when they arrive. Could it possibly be something else, like the ecm?

 

Are you getting any codes for the trans?

 

No. Nothing showing on the dash

 

May need to plug in with a good scanner, and see if there are any pending codes.

Are you seeing the 'trans temp' light in the dash? Does O/D mysteriously turn itself off? (and THAT light in the dash comes on?)

 

No, no warning lights on the dash at all.

 

Check for pending codes, see if anything comes up. Local parts store might be able to help you with that.

 

P0740 Torque converter clutch circuit

 

And that may be enough to screw things up..... Clear codes, see if it changes anything.

 

Replaced the solenoid and sensor. Problem solved. Drives even better than before. Thanks for your help!