Dealership said they had great luck with the 2wd by just changing the tires to a different brand. 4wd they haven't had one in the shop, mines the first one. I Called around to the other dealerships and most of the 4wd they think to fix the issues is changing the tires and shocks to a different brand like they had been with the 2wd but there isn't a gm approved shock or tire that they can use.