my exhaust was vibrating the other week and when i had a look one of the rubber bracket things had slipped loose from the hook the other end was on, when i slid it back on it was fine, i blamed going over speed bumps
i think that's what i've described but didn't know what they call those thgick rubber things that are shaped like the letter 8 and 2 little rods push through each hole in the 8 , one rod is on the exhaust box and one on the underside of the car