Don't buckle passenger belt, but rattle happens even with passenger buckled in. As far as grammer definition, makes perfect sense. So if someone tells you you don't know shit, are they paying you a complement or ragging on you? Perhaps it has to do with which word they emphasize.

YOU don't know shit. You don't know SHIT. I often apply this phrase to myself.

 

*chuckles*

Passenger seat belt buckle is one rattle - have you checked that the fuel release cable is securely stuck down?

Also don't forget droplinks and ARB bushes as well as that headlight adjuster on the rear lower suspension arm.

Also check there's nothing fallen down the softtop drain hole

 

I once heard a strange rattle, but then I saw that my girlfriend had been finding loose pennies and putting them in the little net on the passenger door and they were rattling.