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How to Protect Your Catalytic Converter and Pass Your Smog Test

06 Feb 2023 0 Comments

According to the National Insurance Crime Bureau, between 2019 to 2022, catalytic converter thefts increased 1,215%. In light of this staggering statistic, many of us may have thought, “What’s the cheapest option in order to protect my catalytic converter from theft?” 

Some consumers are visiting repair shops to find custom solutions to protect their converters. State Agencies that manage automotive repair and smog programs are adjusting to this new wave of protection devices. They have provided guidance on how to protect your converter without failing the smog inspection. 

The California Bureau of Automotive Repair has specific guidance to protect consumers from failing their smog inspection or damaging their converters:

“Will a catalytic converter theft prevention device impact my vehicle’s Smog Check results?

A vehicle will fail Smog Check if the theft prevention device modifies or damages the catalytic converter or if any required identifying information is not visible. In addition, a theft prevention device should not be welded or attached directly to the catalytic converter. To help ensure the proper installation of a theft prevention device on your vehicle, visit a licensed auto shop.”

-California Bureau of Automotive Repair

While it may be tempting to simply weld rebar over your catalytic converter or fasten materials over the converter, most of these custom jobs may do more harm than good. Aside from not passing your Smog Check, welding can damage your catalytic converter and void its warranty.

Underside of car without shield

While we cannot completely prevent catalytic converter theft, we can implement security protocols to avoid becoming a victim. The best measure of protection to deter thieves is with a quality anti-theft shield that protects the converter and allows you to pass your smog inspection. We recommend Cat Shield™ by Miller Cat, the only true manufacturer of protection shields that is part of Toyota's Associated Accessory Products (AAP) Program and is also a manufacturer of aftermarket CARB-approved catalytic converters.

In an effort to constantly improve and design the best shields on the market, Miller CAT recently launched an upgraded version (V2) of the ever-popular Prius Gen 3 Cat Shield™. This upgraded shield is a complete bolt-on application, which means a shorter installation time and no drilling or specialty (rivet or rivet nut) tools involved. Ours is the only shield that does not require you to drill and permanently modify your vehicle. We’ve engineered an innovative design that will replace 3 existing models, the Prius Gen 3, Prius V, and Lexus CT 200h. Three vehicles, one shield - now with an incredibly easy installation that will not rattle or make noises when installed on a vehicle with an OEM (original or from the dealer) converter. 

Updated Prius Gen 3 V2 shield next to old models being replaced

Pictured: New model (left); previous models for Prius V, Prius Gen 3, Lexus CT 200h (right, from top to bottom)

We also offer shields for the Prius Gen 1, Prius Gen 2, Prius Gen 4, as well as the Prius C. Available in different materials, including 304 stainless steel. As a trusted partner of Toyota’s Associated Parts Catalog, Cat Shield™ offers the ultimate strength and deterrence to protect your vehicle. Restore your confidence to drive and park again.

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