I have recently bought a 96 cherokee country, and I noticed that when it idles/low rpm there is a vibration coming from underneath the car. I asked the guy what it was and he said it was a broken exhaust hanger and the exhaust is vibrating against the bottom of the car. When I checked it out today I figured out it wasn't that it sounds like there is something bouncing around inside the cat. What can that be? Advance auto said 147 for a new cat and if it is that is there a place I can get cheaper? one more thing, I plan on getting a new exhaust anyway, but this might set me back a little, but should I get a high flow cat now or does it sound worse?

Thanks for any replies in advance..

 

get a high flow cat..check out summitracing.com I got a magnaflow which run about $95 for a direct fit. Universal fit is cheaper but requires welding.