[biketopia]

functioning cats will knock down any chance of a fuel odor. Having no cats and a fairly aggressive cam can really make it more pronounced at idle. If you're a stock engine, it won't be terrible, but if you have em and the shop can put them in for you, it certainly won't hurt anything. It will also help to keep the truck quiet. Hallowed out cats can actually make your exhaust a lot louder as they act like an expansion chamber.