[JL8Jeff]

I haven't had a full size Chevy, but I've cranked up the torsion bars on several Toyota trucks and 4Runners to get an extra 1-1.5" of lift to help level the truck. I never had a problem. If you try to crank the torsion bars for 2-3" of lift and put 33" or larger tires on, then you're really messing with it and way past what the original design was supposed to handle. If you're only looking for minimal adjustment, the torsion bars won't be a problem. I'm not sure what these "keys" are but it sounds like they might be a quicky fix as well and not engineered like a proper lift kit.