One other thought about this. I've mentioned before if (when, actually) the front mounting pads in your truck get compressed too much, they let the cab rest on the frame/frame mounting pieces. When this happens it will telegraph all sorts of noises and vibrations inside. The replacement pads are not correct...they're too compressible and only last a few months before creating the same problem. The only answer I've found is to buy a bit of the gray pvc sheet used for shower pan liner and cut it into pieces about 2" x 3" with a hole punched or cut in the center. You need the cab to sit 2.5mm to 3mm above where it mounts to the frame. In the front that is. I have not seen this as a problem in the rear. A couple of weeks ago I posted an image I made of mine...not certain where that post went.
