I have a 2001 cobra, As of the last week whenever i go over 40 my car starts to rattle. And it gets progressively worse the faster that i go. When i press on the trottle it kind of goes away, but it rattles alot when i take my foot off. What do you guys think that It could be, I checked my tire preasure and their all the same. Any ideas?

 

your tires are cupped

 

or out of balance

 

get your tires balanced, check lip of rims for bends, hit any potholes?

 

+1. when first got my car it rattled like crazy on the highway, then got the tires balanced it was gone completely. but it could also be a bent rim. my brothers car has a bent him and his rattles like crazy on the highway

 

if the tires are cupped there will be almost no way for you to tell, but you should feel a wavy pattern in your hand over the tread