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
Lola: ABM, 2LT/RS, #1848 of 3903 and 1 of 29.
"HID" BLue Headlight Armor, Gen5DIY DRL LED's, Gen5DIY DRL Harness, CAI, 35% Tint, RX Catch Can(ABM) & Oil Filler Cap Breather(ABM), Custom Blue Bow-Ties, ZL-1 Springs