[Gaetan Anderson]

so I swapped in a 2000 Bonneville engine and trans plus HD axles and I got the car to run and the 2004 LeSabre PCM but the transmission would not shift rather than buying expensive transmission and have to rip everything out again I thought why not get the 2000 Bonneville PCM that matches the engine and trans, because the lasabre and Bonneville are both hbodys so the electrical is the same so I got a used 00/01 pcm and gunna give it a try, I know that the vins won’t match but I’m hoping It can still work besides a couple codes. Tell me your thoughts I havant been able to get to my car to plug it In yet and I’m over thinking things and I jus need my vehicle back and useable.

 

[dezldave961]

Didn't you already post this elsewhere? Or am I going crazy with similar topics and recurring questions?

There's always some considerations to take into account when swapping between various 3800/4t65 varieties.

4T65-E ID Charts

The wiring harness to the different Internal Mode Switch (IMS) transmission types will also be an issue. The non-IMS style has a shifter position module on top of the case around the shift post with added harness connection, while the IMS type has everything internal and thru the main circle harness to the transmission.