Ah, the Avalanche...this was my first Truxxx truck, a fully loaded (base model with leather by today's options!) black on black SUV the world loved or hated...I loved it, perfect for driving, hauling dirt bikes, I camped in it and wore out three sets of tires in two years! It spent so much time on the highway I got over 100,000mi. out of the OEM brakes and front end, and we lifted it with less than 100mi. on the odometer! This was the beginning, going door to door, shop to shop in 2004 NOBODY had heard of a leveling kit because we had just created the first "line" of kits - I got all these questions, your ball joints will die, your CV axles won't make it, you can't fit 33's on a Chevy without 6" of lift....if you could think it we heard it....it was a lot of work! It was funny, nobody believed me until we went to the parking lot, I threw them the keys and they drove it...it drove like stock...but it had 33's! This kit has torsion keys, and it took us a small dumpster of "scrap" torsion keys to get the degree wheel figured out and the math written for the angle and then it was figuring out what steel would work best, we tried all different types, some would spin, some would crack, some were impossible to buy enough steel consistently and the real kicker was CAST was garbage, they kept breaking on our "jump" test...yes, the Av got air more than once and we bent a wheel or two...but the keys gave us 3" more wheel travel as well as 3" of lift and we were getting air and parts didn't break! Looking back, we were nuts...today, the segment of the market we created is huge...it's crazy to think how many leveling kits are out there that would never have happened if it wasn't for the AV.... It's amazing what a few inches will do :-}