Dorman is notoriously poor quality so I wouldn't worry too much that you didn't buy those. Get the OEM parts while you can! GM is discontinuing everything faster than I can buy what I want to have on hand. There is no bearing in these struts and there isn't much to the upper strut mount, I didn't replace the mount on either of my trucks and have no issues but I will probably replace them if I ever take the assemblies apart again for my perfectionism.
The new springs make a MASSIVE difference in the ride quality. New springs raised my 2008 3/4" and raised my old 2012 a full inch. I didn't pay attention to what it did to the 2013 because I did it at the same time as the 2" drop knuckles. I wish I had known GM was going to discontinue the springs or I would have bought an extra set or two to have for down the road, I bought the last two in the country for the 13. My father-in-law told me his 2008 Sierra Denali has been riding bad lately and his front springs are still available, surprisingly, but he's decided to buy my Atomic Fab/Viking coilovers, new leaf springs for the rear, and we'll order the matching Viking shocks for the rear. I can't wait to see how his feels after. I liked the coilovers on mine, but I never got to experience the full setup with the matching rear shocks since I decided that I didn't want to lose the auto leveling air suspension.
