I have a 2006 Sierra 4x4 I am thinking about dropping in a L92 out of a 2007 Yukon. I have read several posts and some say it’s pretty well a simple drop in with minimal changes needed, others make it seem like rocket science. I will be leaving my 4L60e in to begin with but would like to know what all it would take to swap in a 6L80e later on. Some posts I read were saying you can use your 5.3 wiring harness and ECM but some were saying otherwise. I would love to hear from someone who has done one of these swaps.

Thanks for the input. I’ll look into the LQ9. Would a LQ9 swap right in and be able to use the wiring harnesses and ECM?

Im guessing the LQ9 would be the easier route then. Would there be a big difference between the lq4 and the LQ9? I see it’s about 35-40hp but from what I have read that’s mostly in the tune? I also read where if you go with a lq4 to go with a 2005+. I have a 5.3l and recently put a tsp 212/218 low lift cam, tsp lt headers with ORY, CAI and got a dyno tune, I never received a print out but the guy says it’s putting 308 to the rear wheels. I’m skeptical, it does have more power but I’m not satisfied and I don’t think it’s pumping out over 300hp.

how about the tsp 212/218 low lift? Would that be better than the stock cam? If I end up doing the swap and that cam will work I will pull it out of my 5.3 and just put the stock cam back in and use that engine in my 85 Silverado.