I have a 2011 LTZ 4x4 with all options, tow package included. I'm looking to level it out, but unsure on height for front/rear. Would 3.5" in front and 1.5" in rear be about right? It does have the automatic leveling system
Have a tape measure? These things all sit differently and can change between drives. Measure how yours sits and order what you need to put it where you want it. I'd advise against just going off numbers, though. A slight rake is more ideal than level and level might look slightly squatted due to the body lines.
Measure yours. Then jack up the rear an inch at a time and step back to assess. Once you like where the rear sits in relation to the front, measure the difference and order the parts accordingly.
Without measuring, it'll all be a crapshoot.
If you have ALC, you just need to make longer links for the sensor rods to put the sensors back where they were when it was at stock height. With it sitting on a level surface at stock height, before you do anything, mark the sensor locations at each corner so you'll have references to aim for when making your links after the lift.
Mine with the stock link and reference marks, misaligned cuz I lowered it:
Realigned by making shorter links out of stainless 10-24 all thread rod:
Lifting would require longer links.