So how would I go about fixing a rear plate rattle?

 

Maybe tighten it..

Or if that doesn't work, take it off, bend it slightly so that the side that is rattling is solidly against the car.

 

that have these foam pads that you use to seal things.... they have adheasive on one side and foam on the other.... i know there are really thin ones so maybe you could stick that on the back of the license plate where it is rattling against your car... Get it from k-Mart or home depot ect.

-Dakota

 

I used some 1/4 thick foam tape (one side is stickey) then put it on the back of the plate and no more rattles.

 

Thanks for the ideas.