Does anyone have an explanation why the rear corners of the cab is mounted to the frame with shackles rather than bolted to it like the front of the cab? Is the intent for the shackles to allow the frame on the left and right side to flex up and down in the rear independent of one another? Like turning right over a curb, allowing the right frame to flex up while the left frame stayed straight. . . kind of alowing the cab to float on the frame. The reason I wanted to know is because if the frame is supposed to move up and down different on the left side than the right side then it would make sense that cross members in the rear should not be welded but rather bolted on the bottom side only. Welding a cross member will (it seems like) make the frame rigid.
Any thoughts about this? The reason I ask is because my frame rail on the right side is slightly higher in the back than the left side. I think this happened when we welded in the upper shock bracket to the left and right frame. If this is causing a problem then I'll cut the welds and attach the shock cross piece in a different way than welding it to the left and right frame.
