I have been battling trans issues on my 2002 4.7 1500. I used a scan tool and the following codes came up: P0867 Line Pressure Fault, P0733 3rd Gear Incorrect Ratio, P1790 Fault Immediately After Shift, and P0876 UD Pressure Switch Check Failure.

This thing had wiring issues when I got it. I have repaired all of those and everything checks out as it should as far as wiring. The power wire to the TCM was bad as well as the ground to the speed sensors. Those have been repaired. During the initial troubleshooting, not knowing I was missing power at the TCM the following were replaced. TCM, both speed sensors, pressure sensor, and valve body/solenoid pack/TRS. Once I repaired the wiring it drove fine for about a week now it is slipping and it progressively got worse. First it would just slip in drive when you hit about 30 MPH's. You could drop it to 2nd and it would drive fine. Now it doesn't matter what you do it barely moves. I am wondering if it could be any of the items I replaced, but I do not have that much knowledge of the internal workings of a transmission. If anyone can lend me any insight before I tow it to the transmission shop please let me know. Thanks