L31 to LS1 swap in my 99 Yukon

[MatthewJB]

Hey guys just a few questions with this swap I'd like to do. 1. will my stock 4l60e work and bolt up directly to a Ls1 block or would I need to get a new transmission and/or adapter. 2. If it will work, would it work with a LS1 wiring harness and PCM? 3. Where can I find a reliable site to order parts for this swap? thank you in advance for answers tips and tricks!

 

[Schurkey]

Perhaps a moderator will move this to the LSX + Carb Swaps sub-forum.

 

[L31MaxExpress]

Hey guys just a few questions with this swap I'd like to do. 1. will my stock 4l60e work and bolt up directly to a Ls1 block or would I need to get a new transmission and/or adapter. 2. If it will work, would it work with a LS1 wiring harness and PCM? 3. Where can I find a reliable site to order parts for this swap? thank you in advance for answers tips and tricks!

You will need a flat flexplate, a spacer and longer bolts for a 2004ish LQ4, then the converter bolt holes will need to be elongated. I would just get a LS style 4L60E at a minimum. Personally I would ditch the 60E and get a 4L80E though.

You could probably trade off the LS1 for an iron 6.0L too, which would work better for the swap. The truck accessories, intake and exhaust manifolds are an easier swap into a truck.