I have a 1996 Cadillac Sedan Deville with the northstar engine and automatic trans. The problem is it wants to start out in 2nd gear instead of 1st. It shifts good other than that. It still wants to start out in second even if i pull it down in 1st with the shifter. Any help would be appreciated.
it would be more accurate to say that the 4T80 was basically a clean sheet design. there is probably nothing between the two that will interchange.
4T60 and 4T65 are related, but the 4T80 doesn't seem to have anything common with either of them. the 4T40/4T45 seems to have a few design cues from the 4T80 though, but obviously significantly weaker.