I was finally able to get my truck on the lift and noticed the 2 bolts that hold the rear of the cab to the frame were missing. They look kind of strange i dont know what to do to install new ones. Should i get them from chevrolet? they dont look like they have a nut on them. Honestly I don't know how they work. The truck makes a creaking noise going around a turn. Has anyone had this happen to them? Thanks