It's odd that not all "heavy duty", over 8600#GVW got these "cats". Most of the trucks at work have them but not all. The emission label under the hood will give it away.
Another way to beat the smoke test is to make the truck unsafe to run on the dyno. If you have something heavy bolted onto the truck or over hanging it won't or shouldn't go on. In my area I can ask for a two speed idle test. If you have a smoker it has a much better chance of passing in park instead of under a load on the dyno. It really has to be smoking pretty bad to fail
My plans exactly, gut the cat and make em think one is there. Actually, my dads plan is to use the old 3.5 inch exhaust system of his truck. It has a resonator that looks like a cat, but isn't and is a half inch bigger than the system on my truck.
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