The bullbars are mounted horribly. mine did the same and ended up taking the paint off it where it rubbed on the guards. Nissans only answer is to tighten it back up... Most bullbars (arb etc) are mounted over the chassis rails with a bolt done the middle or atleast a plate over the top of the rail to stop it tilting but the factory bullbars are only held in with 4 bolts... Mine have elongated and when i went to use the hilift on the bar it pushed the bar up into the guards....scary seeing as i snatch and winch off the bar... I still havent found a way to reinforce the mountings will have to look at it soon.