Hey guys, 07 F150 Lariat Supercrew i get a shimmy and vibration though the drive line and the steering wheel when i am hitting bumps in the road. The ride quality has went down a tonne since I got it any similar issues out there? I had it checked and they told me it was the pirelli tires because I have the aluminum 20's, changes tires to goodyear wranglers, still rough had the dealer change the steering rack and the was little change??? I am in edmonton canada and we have some bad roads but 65k?? Any shock upgrades to look at? I am also getting a bad vibration on deceleration at high speed/rpm is that the univeral joints?

Thanks