Engine/Trans Swap 2004 Donor to 2000 Body

Silentreyn · May 21, 2015

Good morning, everyone! I'm new to the board but I hope to frequent it pretty often instead of being one of those one and done posters.

So, here's my situation:

My 2000 Silverado 1500 z71 transmission is getting pretty tired (215,xxx miles) and I've picked up a wrecked donor 2004 Silverado 1500 with a rebuilt transmission that I know to be functioning well. Both have the 5.3L with the 4l60e trans.

I'm looking to swap the engine and transmission from the 2004 into the 2000 - my thought is everything will bolt up properly due to not much changing between 99 and 06.

My concern is can I use the pcm from my 2000 on this newer engine that we're putting in or will it require a new wiring harness and pcm? Are there any other things I should be concerned about?

Thanks for your time!

Reyn

wilsonz71 · May 27, 2015

Good morning, everyone! I'm new to the board but I hope to frequent it pretty often instead of being one of those one and done posters.

So, here's my situation:

My 2000 Silverado 1500 z71 transmission is getting pretty tired (215,xxx miles) and I've picked up a wrecked donor 2004 Silverado 1500 with a rebuilt transmission that I know to be functioning well. Both have the 5.3L with the 4l60e trans.

I'm looking to swap the engine and transmission from the 2004 into the 2000 - my thought is everything will bolt up properly due to not much changing between 99 and 06.

My concern is can I use the pcm from my 2000 on this newer engine that we're putting in or will it require a new wiring harness and pcm? Are there any other things I should be concerned about?

Thanks for your time!

Reyn

Welcome to the forum.

Ive done this swap you're thinking of but the other way around. From my experience, to use your current wiring harness you will have to keep your oil pressure switch (they are different 99-02/03-07), throttle body (cable vs drive by wire), and your erg parts. You could delete the egr but risk an engine light. When we did it, no computer tuning was necessary. Good luck with the swap, its not too hard of a job.