I just go get some 4inch from the local peterbuilt dealer and some fittings as well to go from 3 inch to 4 inch and then make custom hangers out of straight rod get a turn down tip for 20 bucks and dump it under the truck before the axle. That works wonders. and will run ya about $60. Or you can just get 3 0r 4 inch and just cut out the cat and the muffler and fill in, keeping your stock tail pipe, this you can usually do for about $40 and works well for the time being.
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