I tried everything that these guys tried and more. I've got steel bolts going thru the plastic below the window, greased everything (nothing will ever rust on this truck for eons), replaced , tightened screws, etc. I've got one more thing that needs to be tried. A friend that has a new HD ( whatever that designates) Chevy said he had the same kind of noise. I told him that Chev's always rattled after 10 miles on odometer. He said that I needed to ride with him. The noise was the same, or close with my hearing. He said that it would be fixed the following day. Sure enough it was gone. So were his Smittybuilt step bars. One of the mechanics that he goes to mentioned that on some vehicles these step bars were causing a squeak. No one could explain why, as it doesn't do it on all trucks. I haven't had a chance to take the steps off yet, but if that is it I'm greasing them upon reassembly. If the squeak comes back, they're history. If that doesn't do it I'm getting a giant subwoofer and I won't have to listen or worry about it again.