I went with the Ready Lift level for AT4X since it replaces the UCAs also. Weird that this link used to say “compatible with AT4X” and now says it isn’t?! Kinda odd but I don’t seem to have any issues with it.
1.75" front leveling lift for 2019-2022 GM AT4 and Trail BossNow works with Sierra AT4X or Silverado ZR2 Edition.Includes DOM tube steel upper control arms withTCT maintenance-free pivot bushings and 1-ton ball jointsCNC machined aircraft-grade billet aluminum top and bottom strut spacersAT4 -...
www.readylift.com
Went with 285/60r20 Nitto RG (33.7”x11.5”) and Fuel Rebel 20x9 +1. Had slight rub but removed mud flaps and minor trimming and all good.
Would recommend an offset wheel of +10 to +20 for better angles when turning to fit larger tires. I would have gone with a +18 if I did it all over again.
Thanks and hopes this helps!