I just had this vibration in my truck and it kept getting a little worse. I thought it was the center support bearing on my rear driveshafts so I ordered one from the dealership. When I recieved the bearing I took my driveshafts out only to find that my rear u-joint was the problem. Now I have a brand new bearing that I cant use and cant return. You may want to check the bearing and u-joints in your truck. If you do need a bearing I will sell this one cheap.