I know this isn’t going to help alot but when i was looking at buying my truck, I couldn’t believe the amount of parts that they replaced right after it was bought new. There is no doubt it had the shake. They changed the front differential, drive shaft, tires and more. I honestly cant even remember all the stuff they changed. In saying this, this truck drives and rides really good. I believe this shake issue can be fixed or mostly fixed but im guessing its an expensive fix due to the list of items they replaced. This is also on junk Goodyear LS2 that are approaching the end of there life and has multiple plugs in multiple tires and have never been rebalanced. If anyone wants to send me $39.99, id be glad to grab the carfax and post it so everyone can look at it