1989 Suburban with 5.3LS/700R4

[Firebirdjones]

Interesting swap. I'm a 6.0 fan myself but that 5.3 should work nice for you. Too bad they didn't swap in a 60E instead of that 700, then you would have total control of both the engine and trans with simple key strokes
It will take alot of trial and error on the 700 to get the shift points in a happy spot for that 5.3.

If you had HPtuners I could send you a stock 5.3 tune file so you could flash that in to start with. I can tell you though they need alot of time tuning and tweaking to optimize even a stock engine.

Neat truck, and a good deal considering the coin it takes to do an LS swap and do it right. You'll have some fun with that.