When it comes to replacing your ride’s faulty catalytic converter, you have two options: spend a small fortune at the dealership or save a bundle by doing the job yourself with an aftermarket replacement. Before you rush off to the garage, remember that not all replacements are street legal in all states—and they’re not as easy to install as a set of floor mats. If you want your at-home install to go smoothly—and not raise the eyebrows of your local smog sniffer—you’ve come to the right place. Our guide on selecting the best catalytic converter breaks down the key information to get the best aftermarket cat for your car, truck or SUV.
Identify What Emission System Your Vehicle Originally Came With
First things first, it’s important to know what type of emissions equipment came on your car from the factory. To do that, you can pop your hood and check for an emissions equipment sticker. Typically these are located under the hood or near the firewall area behind the engine in a visible area. States can either follow the federal standards set by the Environmental Protection Agency or they can adopt the stricter California Air Resources Board regulations.
- If your vehicle was originally sold in California, it will have emissions equipment that meets the CARB standards
- If your vehicle was originally sold somewhere outside of California, it may or may not be equipped with CARB-acceptable equipment—it depends on whether the state follows California standards. Check that state’s DMV site for more information.
What State is your Vehicle Registered In?
Now that you know what type of smog blockers came stock, it’s time to consider where your vehicle will be registered. Every state can choose to follow the EPA’s standards or California’s standards, and your catalytic converter has to meet the standards of your state.
- If you plan on registering your vehicle in California, you must use a catalytic converter that meets CARB standards
- If you live in New York, aftermarket catalytic converters also have to meet CARB standards
- If you live in any other state, visit your DMV (digitally or physically) to find out whether they require aftermarket cats to meet EPA or CARB standards. Generally speaking, 49-state converters typically fulfill emissions requirements in these other states, however emissions laws are constantly evolving and they could be different from the time this material is published
What is CARB?
Short for the California Environmental Protection Agency Air Resources Board, CARB is a regulatory agency responsible for maintaining healthy air quality and protecting residents from toxic air contaminants. It was created back in 1967 under Governor Ronald Reagan in response to Los Angeles’ severe smog problems, and it has set the high-water mark for controlling vehicle emissions-based pollution ever since.
Although governed in California, other states can follow CARB standards or stick with the more relaxed EPA standards. So far, the states that have picked up CARB include Arizona, Connecticut, Maine, Maryland, Massachusetts, New Jersey, New Mexico, New York, Oregon, Pennsylvania, Rhode Island, Vermont, and Washington. Even the District of Columbia has jumped on the clean air bandwagon.
Direct Fit vs. Universal
- Direct-fit catalytic converters are engineered to match the cat that came on your vehicle, from the diameter of the tubing to the placement of the O2 sensors. They generally bolt directly into place with no welding, and they’re the easiest to install. However, they’re only available for a select number of vehicles
- If there’s not a direct-fit catalytic converter available for your vehicle, you can always go with a universal replacement. You have to measure your existing exhaust and might have to weld it into place, but they generally cost less. Just make sure it has the right sensor ports—they last thing you want to discover after it’s welded into place is that you need to bung it