Add me and my 2LT/RS to the growing list. It's a 2010, picked it up 3 weeks ago and noticed the problem right away going over a speed bump after picking it up.
Had less than 2800 miles on it when I got it.
Description of the noise is nearly verbatim of what i read in this thread so far.
United States Army Air Cavalry
ABM, 2LT/RS, #1848 of 3903 and 1 of 29.
CAI, Gen5DIY DRL LED's, Gen5DIY DRL Harness, 35% Tint, RX Catch Can(ABM) & Oil Filler Cap Breather(ABM)
To Do: SS front end, drop springs, Nickey Stinger Hood, polished ZL-1 style wheels, BBK long tube headers, ARK N-II cat back, OE GFX, painted shark fin, and on and on and on....