Noise From Under A Brand New Truck-need Help

[brian12c]

I installed 2" drop shackles on my 07 classic and now i get a rubbing noise from under the bed, below the rear of the cab (reg cab). I hear it when I come to a stop or slow down quickly and sometimes when I go over bumps. I think it may be the rubber supports that hold the bed on the frame but Im not exactly sure. Im also not sure it is due to the 2" drop. I didn't install drop shocks. It seems like its coming from the far left side of the truck. I tried loosening and tightening the newer shackles but I dont think they are the problem. The truck has less than 4k miles on it. Anyone else have this problem? Any help is appreciated.

[lerbud]

it probably the shackles hitting the bed if you put the shackle bolts thru the top holes. i always had to use the lower holes in the shackles to keep them from hitting the bed.

[brian12c]

Ill check that but I doubt that is the problem. It doesnt sound like a metal on metal sound, more like something under tension or pressure that is rubbing. thanks