I have a 2011 Town and Country that had the front head go bad which was replaced. It also gave me a catalytic converter error. So i replaced both the front and back converter with after market parts because the OEM converters are expensive. After replacing them the dealer could still not get the error code to go away. The Dealer had my van for two weeks, resulting in them telling me that on that my particular van you can not put after market catalytic converters on them. I was wondering if you have heard of that issue with the catalytic converters?
I had the same thing on a Jeep grand cherokee. I had to have the heads replaced for free at the dealership as well but the other cat error went away so you probably did not need to do anything with the cats. With the bad heads it was probably getting some coolant in the exhaust. I called a good muffler shop here in SC about it (I have since gotten rid of it thankfully) and they said a generic cat is fine but you probably did not have to do it at all. I think it has 2 cats. Find a good muffler shop where you live and ask them.
For the sake of argument, I am assuming the cats need to be replaced, and that it is a problem upstream (or less likely downstream) from the cat. (It could very will be another problem where the cats don’t need to be replaced.)
With that said, theoretically and technically speaking, as long as the cat matches specs of the OEM, it should be fine. Just chop off the cat, and weld in the new cat. A cat is a relatively passive device with no moving parts (unless you count the chemical reactions of the metal with gasses as “moving”).
On the other hand, legally speaking, depending on the state you live in, for example, California. The cat needs to have a special stamp on it to make sure it is compliant with state emissions laws. And this usually is only direct fit OEM.
So yes and no, depending on your state, you can install aftermarket cats.
