prostar cab shocks/ bongo drums

Cab sounded like somebody beating the bongos from right rear of bunk whenever the truck was moving, was driving me nuts! I had on different occasions someone rock the cab back and forth so I could listen and try to figure out where the noise was coming from, traced it to the right cab shock. grabbed my tools and replaced that shock. Soon as I pulled out of my shop noise was still there! UGGGGGHHHHH. Thought about it overnight so Sun. I unhooked the leveling rod, worked the valve by hand and raised the cab higher than normal, blocked the cab up, released the air in the bags, took the two horizontal bolts out that hold the u-shaped bracket to the bottom of the cab.{nuts are welded on the backside so they came out real easy},pryed the whole assembly down about an inch and lubed all the metal, bolts and all with spray grease, reassembled and VOILA....noise has disappeared. Even though those bolts were super tight, there still must have been enough play there to make a squeak and banging noise. Hope this will benefit anyone who has this issue before you invest $350 on a new shock. {I didn't by the way, I found a pair of new shocks for $100 each, long story...}