How to Really Prevent Catalytic Converter Theft

If a thief is determined to steal your converter, it does not matter where you park your car and what you etch on your converter. We receive countless testimonies of people parking their cars in garages, using alarms, or other security devices only to have their catalytic converters stolen. Converters are extremely enticing for criminals to steal because they are worth so much, can be stolen in minutes, and extremely hard to trace. With a struggling economy and rising commodity prices, it is difficult to see this trend of theft waning in the future.

Stop Catalytic Converter Theft from Happening to You

These days there are a growing number of products you can buy to help prevent your catalytic converter from being stolen. They come in various shapes, sizes, material, and fastening methods. However, each product can be graded by these three factors: material, shape, and fastening methods.

Materials Used in Catalytic Converter Shields

Material: Catalytic converter shield and security devices come in various metals. Aluminum, steel, and stainless steel. There are advantages and disadvantages to each of these materials.

Aluminum: Probably the most common material used in catalytic converter shields and guards because it is relatively cheap, lightweight, and anticorrosive. However, aluminum is probably most effective at being a visual deterrence for thieves than an actual physical deterrence. Most of the times a thief will see a shield and leave, but if a thief tries to cut through it, the aluminum can be cut through given enough time. Thicker aluminum (.190") can gum up a sawzall, but thinner material is less effective at stopping a blade.

Steel (carbon/mild steel): Not to be confused with stainless steel, is a common material for skidplates. It is a cheap, heavy material, but is more prone to rust and easier to cut through than stainless steel. The main drawback is its limited anti-rust properties compared to other metals.

Stainless Steel: Is a hardened material that has high anti-corrosive properties. This is the most ideal material for catalytic converter shields, guards, and protection devices. 304 stainless steel will burn out the strongest sawzall blades paired with the best saws on the market. Here's a quick video to show how amazing our 304 stainless steel cat shields are!

304 Stainless Steel Cat Shield by MillerCat

Shape: The most common catalytic converter shields you might find are flat pieces that are fastened to the underbody of the vehicle. While these are common type of guards (because they are easier to manufacture), they are also limited in their effectiveness at preventing catalytic converter theft and noise. This is because flat shields can only protect so much of the converter and also do not account for the angles and motion of the exhaust system. Typically the more complex the design, the more engineering and effectiveness of the product.

Additionally, while vents and logos are great to add to a product, they are also a vulnerability. Shields that have simple cut outs or large logos give thieves a headstart in cutting a shield and may actually encourage such behavior. There are better ways to increase airflow and show off your logo, such as using louver vents and stamping your logo.

Fastening methods: Some catalytic converter protection devices will permanently fix the cover to your vehicle while others provide screws and a key to remove them when you need to. Drilling and using rivets is the cheapest way to attach a shield, but will cost you in the end when any type of maintenance needs to be done to the exhaust or O2 sensor. It can also cause galvanic corrosion which will eat away at the frame of the vehicle, shield, and fastening hardware. Security screws are ideal to give the ability to maintain the vehicle and protect it. However, most companies will say they have tamper-proof/resistant hardware, when in fact, they are not. Most companies use a 6 lobe screw with a pin. These can usually be found at your local hardware store or tool box.

Catalytic Converter Theft Prevention

Miller CAT's expertise in catalytic converters, manufacturing, and research and design helps make them the most advanced and strongest deterrence in catalytic converter protection. They use different materials based on the level of protection and offer the strongest material on the market (304 stainless steel) for some of their applications. Their designs are more advanced and address the weaknesses found in other designs. Finally, Miller CAT is committed to using the least common fastening hardware out there to make sure customers will have the ability to maintain their vehicles while also protecting them from catalytic converter theft.

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Tendrán escudos protectores para Hyundai Santa Fe 2022 o piensan producirlo??

Luis Roberto Alvarez Fernández

I’m sold on your product, but I do not think I see a shield for my vehicle.
Any chance you may make one for a 2010 Lexus ES 350?


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