97 gmc manual

[97 gmc]

I have a 97 gmc Sierra 4.3l manual and got my hands on a 99 chevy 4l60e automatic. What will it take to swap them ? Plan on a floor shifter for the 99 automatic 

[richard wysong]

You gonna swap both of them? Which 1 are you changing? If you are putting the auto ln the 97 you will need to change the wiring harness and the ECM.If you are putting the standard in the 99 at the very least the pedal assembly and maybe the ECM. Sounds like more trouble than it's worth! Driveshaft is probably different as well

Edited October 18, 2023 by richard wysong

[diyer2]

Can of worms nowadays with the electronics. 

[richard wysong]

Welcome to the forum! If you want to change the 97 to an automatic I would look for a non electronic trans like a TH350. A 700R4 would also work but the converter lock is electrically controlled by the ECM