so if i swap out my 5.3 to an l92 will i need to flash the computer if i use the ecm that comes with the l92? i have a 6l80. in my mind it seems like a direct swap but im looking for anything that I might miss being a noob

 

You can send the ecm to any mail order tune place like Black Bear, limeswap, etc and they'll put a base tune and unlock it for $100 otherwise it won't start.

But I think you can use you're stock ecm and it should run, then you can drive it to a professional tuner.

 

The TCM in the transmission will not match the PCM if you used the L92 computer.

Pretty sure you'd have to have a dealership flash the computer for you.

I'd just mod the 5.3 myself, seems way cheaper and less hassle.

 

im not sure why the tcm comes into play, if both pmc's control 6l80s that should be a wash. if the engine comes with a pcm and its harness shouldnt it be a direct swap?

 

The way I think I understand it, is that the VIN on the PCM needs to match the VIN on the TCM for them to work together without any issue at all.

So because the PCM from the L92 does not have the same VIN number as the TCM in your truck it will not work unless you change the VIN's at the dealership or someone with a TECH 2 scanner could try.

 

use the 5.3 pc that came with the truck. have it tuned for the 6.2

 

ok, well i live in Maine so there's pretty much no tuners around that i trust. can i get a mail order tune sent just to get it running?

thank you for the clarification

 

This swap is very easy you don't need to use the 6.2 ecm just get a new tune when you put the 6.2 in. And having the 6.2 is way better then that 5.3 any day any mod. Very much worth it! If I was you since you say you don't have any reliable tuners in your area is call up Nelson Performance. They will send you out a tuned e38 ecm with your vin and all you would have to do is swap the new one for the old one. Everything will match and you will be good to go. No down time just call them up order a tune and they send you a ecm and you send yours back when you get it. Simple

 

well thats awesome, thank you very much

 

Any updates on this swap.