I need to make sure I am thinking correctly here.
I have a 00 sierra that I plan on doing the 60 to 80e swap. I understand the part about just moving a few wires and running the wire for the extra speed sensor.
My question is about the ecm. Can I get a ecm from the same year 2500 that already has the 80e tune and use it instead of doing the segment swap?
Or is it easier to use the relay method and run it off the 60e tune?
Anyone have that diagram?

 

Easiest is just get it tuned. Even if you get an ecm it would have to be tuned. Don’t know much about the harness. I did 6.0 swap also when I swapped trans so a tune was needed either way for me. I’m sure if your going 80 your doing other mods.

 

If the gear ratio in the 80e ecm matched whats in my truck I wouldn't need a tune. Just do the key relearn and roll

 

The gears in an 80e are different from what the 60e has internally. You'll need the tune to adjust shift points, etc...

 

I mean the gear ratio in the ecm match the gear ratio of the truck there shouldn't be a need to tune it if I get a ecm from a 2500 that already has the 80e segment in it.

 

So you have a 6.0 pullout from a 2500 going into your truck with the trans?