I have a 98 gt that had a 4r70w in it and it went out and my friend had a spare that came out of a 96 we put it in and the car would go but seemed like it was stuck in 2nd gear no matter what I did and it got up to 5 grand and never changed well I parked it and scanned it and found out the plugs were different changed all the wires in the right spot got rid of all the codes now it doesn’t go forward at all no matter what I put it in but goes in reverse and moves fine