How Do I Know If My Catalytic Converter is Aftermarket?

Posted: January 3, 2023

Here are are the things to look for when identifying Aftermarket Catalytic Converters. We are regularly asked how to tell the difference between aftermarket and OEM catalytic converters. Have you asked yourself, “How do I tell if I have an aftermarket cat?”. Hopefully, we can help answer your question.

How do you know if you have an aftermarket catalytic converter?

There will be common codes with “N” on the units, along with a silver-colored shield with an arrow. Occasionally, there will also be the word “Flow” or “Out” stamped on the aftermarket catalytic converter.

Common Characteristics of an Aftermarket Catalytic Converter:

  • Silver Shield
  • Arrow on Shield
  • Serial Numbers Starting with “N”

Aftermarket parts manufacturers aren’t held to the same standards, though some requirements were stiffened in 2009, so the precious metal content in the aftermarket catalytic converters is often much less than that of the original factory equipment. The lower precious metal content means that the aftermarket converter holds less value than an original manufacturer’s unit when you sell it for scrap metal.

An easy way to identify aftermarket versus OEM converters is through appearance.

If the catalytic converter has a silver metal casing on it with an arrow, that typically means it is aftermarket. The arrow indicates the proper installation direction based on airflow.

We Buy Aftermarket Converters


Common Letters on Aftermarket Catalytic Converters:

Aftermarket catalytic converters are often one of the biggest disappointments regarding catalytic converter quoting. Many people have been able to find aftermarkets and then get the unpleasant surprise of finding out the units have little to no value overall.

These aftermarket cats have just enough PGMs inside of them to positively impact emissions, but not much more. These units are made as inexpensively as possible so they can be more affordable for the 2ndary market but their scrap values decrease significantly when it comes to selling them for end-of-life.

Some of the serial numbers you would look for that will help you quickly identify Aftermarket converters are:
  • Makers: NCE, Bosal, MagnaFlow


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