Top 10 Best Aftermarket Catalytic Converter Review: Buying Guide In 2023

It’s quite a wonder when you are looking for the best aftermarket catalytic converter to upgrade your trucks.

We are aware that one of the reasons people advise against replacing a slowly failing catalytic converter is because of the cost associated with it.

Despite the cost, the catalytic converter remains one of the most essential components in any vehicle.

You will do well to address any issue related to the converter in other to prevent your car from breaking down.


Comparison Table of Best Aftermarket Catalytic Converter [Top Picks]

MagnaFlow Exhaust Products
MagnaFlow Exhaust Products
MagnaFlow 99206HM
Walker Exhaust
MagnaFlow [Universal ]
Catco 608216
Walker Exhaust
Walker Exhaust

what is the best aftermarket catalytic converter? 

In this article, our team of experts has successfully reviewed 10 of the best catalytic converters for the money.

According to our analysis, the best catalytic converter is AUTOSAVER88 ATCC0016 because it was constructed to consistently perform optimally.

The top 10 catalytic converter reviews highlighted in this section should aid your decision-making process.

If you feel lost with some of the terminologies used please refer to the buying guild for further directions.

Top 10 best Aftermarket Catalytic Converter Review 

01. AUTOSAVER88 ATCC0016 2″ Inlet/Outlet Universal Catalytic Converter – Overall Best Choice


Top 3 Features

  • Stainless steel construction
  • EPA certified
  • Non CARB compliant

The AUTOSAVER88 universal catalytic converter is on a whole new level of its own.

It wins the top stop on our list because it has been designed to meet high-quality standards that surpass what is required by OE quality.

Our team of experts strongly recommends this catalytic converter as an ideal choice if high performance is your priority.

Top-notch Materials

The first noticeable feature of this catalytic converter is the fact that it is made from a sturdy heavy-duty steel construction

which ensures that the internal components are protected at all times.

The catalyst coating as well as the internal ceramic substrate have also been engineered to ensure that the product remains as efficient as possible.

Optimum Performance

AUTOSAVER88 ATCC0016 2 has been designed with a honeycomb structure that maximizes the flow rate.

This is a feature many other catalytic converters in the market fall short of.

With this catalytic converter, the unique surface area allows the catalyst to make the right contact with exhaust gases.

Optimum performance is brought about by an increased flow rate due to the characteristic design feature.

Certified for use

The extreme and innovative design feature of this catalytic converter is one of the reasons why it has passed EPA certification.

Every good catalytic converter ought to have an EPA number to reassure customers that they are getting the right product.

However, despite the many positives it is illegal to use in the city of California.


  • EPA certified
  • Honeycomb quality design
  • Sturdy stainless steel construction


  • Not compliant for use in California

02. MagnaFlow 60111 Universal Catalytic Converter – Best Brand & Premium pick


Top 3 Features

  • Quality stainless steel construction
  • EPA compliant
  • Ideal for diesel and gas emission

The Magnaflow catalytic converter has been designed to offer flawless installation at direct-fit applications.

It ensures the hassles associated with finding the right compatible converter for your vehicle are mitigated.

For one, it is built from the ground up to cover a very wide range of vehicles.

Top-Notch Material Build

Megaflow universal catalytic converter cylindrical construction allows it to optimally connect with the exhaust gases from gas and diesel engines.

The improved contact allows for greater airflow which in turn contributes to increased performance of the engine.

Additionally, its stainless steel body prevents rust thereby increasing longevity.

Easy installation

The ease of installation is a critical feature that makes this catalytic converter the most ideal choice for a motorist.

Installing this converter requires welding, tubing, and a host of other small-time professional applications that are widely available with installers.


In terms of performance, we are sure that this catalytic converter will help users pass the emission test in almost all cities in the United States of America.

Be rest assured that you will pass both E-test and visual testing protocols. Once installed, its high performance will ensure that only clean and clear exhaust comes through those pipes.


  • Easy to install
  • Stainless steel construction
  • Universal direct fit


  • Non-compliant with California and a few other States

03. MagnaFlow 93419 Direct Fit Catalytic Converter


Top 3 Features

  • Heating shield and stainless steel body
  • Ceramic substrate material
  • Ribbed design

This Megaflow 93419 aftermarket catalytic converter has been crafted to offer specific professional equipment specifications.

We are certain that the pipe-like design optimally facilitates airflow to improve performance and eliminate harmful emissions.

Uniquely Designed

A close look at the body design of Megaflow 93419 shows that it is not like the traditional catalytic converter in online stores.

However, although many universal catalytic converters don’t require welding or cutting, this converter needs a professional skilled at welding for optimal installation.

Superior Quality

Magnaflow is a rand that places special emphasis on quality.

This heritage is enshrined in the Magnaflow 93419 catalytic converter because reviewers have pointed to the fact that it offers superior quality over a majority of catalytic converters in the open market.

It surely helps to keep out the check engine light off and it also comes in a highly precise CNC robotic manufacturing design.

 Very Safe to Use

The construction of this catalytic converter hasn’t only been crafted to pass EPA certification but the parts are oriented in such a way that it’s very easy to use.

For instance, the cats are oriented by careful design to reach the manifold bolts with all O2 bungs in ideal locations.


  • Reduces harmful emissions
  • Engineered to remove check engine light
  • Sturdy stainless steel body
  • Innovative design


  • The twisted piping design may be prone to leakages

04. MagnaFlow 99206HM Universal Catalytic Converter


Top 3 Features

  • Seam welded close to the converter body
  • Stainless steel body
  • EPA Compliant

A third MagnaFlow catalytic converter makes it to our list of top 10 catalytic converters for the money.

MagnaFlow’s obsession for superior quality has made the brand almost a household name.

It’s no wonder then that this catalytic converter delivers the goods of reducing harmful emissions.

Adaptable Design

Thanks to the adaptable universal design feature, the Magnaflow 99206HM catalytic converter will help keep the engine lights off.

It is a rightly fitting catalytic converter for a very wide range of vehicles but be sure to check your vehicle’s specifications before making an investment decision.

Sturdy Design

Constructed in stainless steel design, this catalytic converter is built to be corrosion resistant; therefore you should be confident of the fact that it will stand the test of time.

It was built to last and there should be no worries of substrate leakages.  The substrate material is metallic and protected by a heat shield.


As a universal catalytic converter, it is built to directly fit into several vehicles.

Nissan Altima models from 2006-2015 as well as Toyota Sienna car models from 2004-2015 are all direct fit vehicles for this catalytic converter.

Finally, the Magnaflow 99206HM meets or exceeds the Federal emission targets set forth by regulatory agencies.

It also complies with the legal use guidelines for OBII vehicles.


  • Superior quality and design
  • Constructed with quality materials
  • Engineered to remove engine check light
  • Good aftermarket replacement part


  • May not come with the steam stickers

05. Walker Exhaust Ultra EPA Catalytic Converter


Top 3 Features

  • Strong and durable construction
  • OE stylish design
  • Direct fit converter

The Walker Exhaust 54582 catalytic converter prides itself as one of the most rugged converters in the market.

We believe that it is a very nice fitting converter for several vehicles and the best part is that it doesn’t require specialized fabrication to fit it in place.

EPA compliant

This walker exhaust catalytic converter is designed to meet the OBDII requirement of vehicles made as early as 1996 and newer.

However, it hasn’t been approved for use in California but it can be used in megacities like New York on cars with EPA-fed equipped vehicles.

 Reduced Emission

Walker’s catalytic conversion is constructed in OE-style innovative technology.

This ensures that it delivers optimal amounts of precious metal load to ensure that the right reductions in harmful emissions are achieved.

Furthermore, it takes care of ay engine light errors that persist in your vehicle.

Quality Design

This converter is originally equipped with aluminized heat shields to match the requirements of OE designs.

The shield functions to protect the carriage from the heat emitted from the converter.

Furthermore, it features thick and ruggedly built hangers, flanges, and brackets to hold it in place.

We are certain that these features will continue to promote longevity allowing users to get the most out of their investment dollars.


  • Direct fitting design
  • Doesn’t require fabrication or welding
  • Strong and reliable material construction
  • Removes check engine light


  • Not compliant with some States

06. MagnaFlow 99356HM Universal Catalytic Converter


Top 3 Features

  • Compliant design features
  • Stainless steel construction
  • Durable welded close

The MagnaFlow 99356HM universal catalytic converter is our third listing of the MagnaFlow brand.

This is a testament to the fact that this brand is at the forefront in the industry of universal catalytic converters for direct fit application.

Excellent Product

The 99356HM is an excellent product choice that can rival any other brand in the competitive market of catalytic converters.

The parts are made from quality products that contribute immensely to the reduction of harmful carbon dioxide emissions.

This converter has also been designed to help turn off the check engine light notification that is common in many vehicles.

High-Quality Construction

Magnaflow’s 99356HM body construction makes it one of the best pieces of catalytic converters in online market places.

The stainless steel construction and the engineering ingenuity are a top-notch feature that sets it apart from the rest of the pack.

Besides, the converter has also been seam welded close to the body for a stronger fit.

Quality fit

In terms of fitting, this aftermarket converter is the perfect fit for several direct-fit applications.

It’s one of the best universal fit converters that can cover a wide range of vehicles. However, professional installations may be needed to make it work perfectly.


  • Nice fitting aftermarket part
  • Affordable converter
  • Reduces carbon emission
  • Removes check engine light


  • Non CARB compliant

07. Catco 608216 Federal / EPA Catalytic Converter


Top 3 Features

  • OBII compliant
  • Quality substrate
  • Built with exact OE dimensions

The Catco 608216 catalytic converter makes it on our top 10 list of best catalytic converters.

The high-performance rating and the quality craftsmanship that went into the production of this catalytic converter informed our decision to include it in our list. Besides, it’s made in the US.

Quality Converter

The Catco 608216 Federal / EPA Catalytic Converter makes use of ARISTO’s propriety chemical substrate to produce highly efficient loadings that are capable of lowering cost.

The reduced cost is economically viable considering gas prices in the market today.

Advanced Technology

ARISTO also employs an advanced technological manufacturing system to craft one of the best catalytic converters in online stores today.

The manufacturing process speeds things up with advanced and automated workstations, welding equipment, and detail-specific production lines.

Without sacrificing quality, the Catco 608216 is built to exact converter specifications.

Top-notch Efficiency

AP’s innovative technology takes things to another level by ensuring that this catalytic converter lives up to expectations.

With an industrial leading efficient system, Catco 608216 catalytic converter is heads and shoulders above other competitive converters in the industry.


  • The high-quality catalytic converter
  • Built to specification
  • Home built in the USA
  • Advanced tech


  • May need slight welding modifications

08. Walker Exhaust CalCat California Converter 80907


Top Features

  • CARB compliant
  • Top-notch quality
  • Consistent performer

The major feature of this converter that caught the attention of our team of experts is the fact that it is CARB compliant.

A majority of catalytic converters aren’t compliant so we thought it wise to include it in our list for those who need their vehicles to pass the CA smog test.

CARB Compliant

One of the best features highlighted in the product detail of this catalytic converter is that it is CARB compliant.

This means that it can be used within California and other areas with strict regulatory measures.

It is designed for use with OBII vehicles made in 1996 and newer.  It can also fit in nicely with non-OBII vehicles made in 1995 and older.

Superior Quality and Performance

There is hardly any contest with this converter when it comes to quality and performance.

The optimum wash-coat technology is carefully formulated to deliver high-quality performance not seen in many other aftermarket converters.

Additionally, CalCat California Converter 80907 converter also employs the use of OE-style coating to deliver constituent performance even in the most rugged of conditions.


To prevent rust and other external damages to the catalytic converter, Calcat is coated with sturdy stainless steel material and with an aluminized pipe.

These two materials combine to shield the converter from heat and other harmful externalities.


  • CARB compliant
  • It has a flexible design
  • OE-style coating
  • Consistent performer
  • Built to pass CA smog


  • No known cons for now

09. AUTOSAVER88 catalytic converter for Nissan Altima


Top 3 Features

  • Heavy-duty stainless steel construction
  • A direct fitting catalytic converter
  • EPA certified

This catalytic converter is another product from AUTOSAVER88 specific for Nissan Altima models made in 2007-2016.

Please, be sure that your vehicle falls within this model range otherwise you will have issues with the installation process.

You should avoid the hassles associated with filing a return.

Sturdily built to last

This converter features a sturdily built stainless steel body with a strong outermost shell that provides maximum durability.

The durable shell also helps keep the internal substrate in place while allowing for maximum efficiency in an all-round performance.

With an internal honeycomb structure, a wide surface area is available to promote maximum flow rates allowing chemical catalysis to occur efficiently with exhaust gases.

 High Performance

The high performance of this catalytic converter is enshrined in the fact that it is capable of clearing out engine error codes.

A majority of check engine errors display a P0420 code that shows that the catalytic system is performing below efficiency.

However, before you think of replacing the catalytic converter be sure to check if the oxygen sensors are performing optimally.

High Flow Rates

One of the main problems with knock off catalytic converters is that they are not optimized to allow for an efficient flow rate of gases.

This catalytic converter allows for efficient flow rates of exhaust gases making sure that maximum contact with the internal substrate is achieved.


  • High efficiency and consistent performer
  • Clears check engine light error code
  • Improved flow rates
  • Built to last


  • Reliability issues

10. Walker Exhaust Ultra EPA Catalytic Converter 54793


Top 3 Features

  • Direct-fitting design
  • Sturdy construction
  • OE-style shields

Finally, a second walker exhaust catalytic converter makes it our top 10 list of best catalytic converters.

This time around the 54782 model direct-fit catalytic converter constructed to be compliant for use in many states in America including New York and Maine.

EPA compliant Converter

The Walker exhaust 54782 catalytic converters are designed for use with OBII vehicles that are 1996 old or newer.

Thus ensuring that you can use your OBII compliant vehicles can be used in places like New York and other cities with strict regulatory compliant levels.

However, you may need to consult with your specific State’s regulatory agency on aftermarket catalytic converters to be sure you aren’t violating any policies.

Direct Fitting Design

To make things easy for new owners the Walker 54782 model has a direct fitting design with bolt-on replacement solutions.

Furthermore, the replacement solution comes with OE-Style hangers, heat shielding, and brackets for very easy installation.

Additionally, unlike other catalytic converters, this model doesn’t require specialized fabrications or welding.

OE-Style Design

To ensure compliance with OE-style designs, the Walker 54782 catalytic converter features an aluminized heating shield system that serves to offer the required protection for the carriage from overheat.


  • Doesn’t require specialized welding
  • Direct-fit design feature
  • OE-style design feature
  • Strong and durable construction


  • May need little modification to fit certain models

The Best High Flow Catalytic Converter: Buying Factors 

This section covers all you need to know about catalytic converters.

If you are in the market to find an aftermarket replacement catalytic converter, please pay close attention to the features listed in this section so that at the end of the day you will purchase something genuine.

How was it made?

The material makeup of the catalytic converter is a very important aspect that you must take into consideration.

How well it is built and the construction design will determine how long it will last.

Ideally, a catalytic box should contain beads within the box that is coated with an ideal material on the inside.

Aluminum and ceria are very popular materials to use. Additionally, compounds like Gold, platinum, Rhodium can also be used.

The Location

The location of the catalytic converter ought to be between the muffler and the engine and shouldn’t be confused with as a part of the engine’s exhaust system.

However, many model vehicles including SUVs come with more than one catalytic converter.

Many trucks also come with more than one catalytic converter because their size is known to contribute to the emission of high levels of CO2.

Subsequently, smaller vehicles will only need one catalytic converter.

Converter Types

Catalytic converters come in various types, thus it’s a brilliant idea to understand the basics of how each of the functions.

The main types of catalytic converters are either two-way converters or three-way converters.

Two-way Converters:  As the name suggests, two-way converters are designed to perform major tasks at the same time.

First, they convert carbon monoxide the CO2 and at the same time convert hydrocarbons into CO2 and water.

Therefore, they are very useful in converting two harmful compounds into less toxic gas.

Three-way Converters: Again as the name suggests, three-way converters carry out three different tasks.

In addition to performing the tasks of two-way converters, three-way converters also convert a third toxic gas.

The Fitting Type

Without the right catalytic fitting for your car, it’s better you never even thought about a replacement in the first place.

You need a catalytic converter that correctly fits the model in your car otherwise you will have a hard time making it work properly.

In terms of fitting, there are two types of catalytic converters; direct fitting and universal catalytic converters.

Direct Fitting Catalytic Converters: With the direct-fit catalytic converter, users can easily bolt it in place at the right location of your car.

Many of these catalytic converters are the best suit for OED vehicles or factory fitted car models.

The rationale for a direct fitting converter is to reduce the degree of modification required to make it work.

Many car owners prefer a direct fit converter for the sake that it reduces installation costs.

With good DIY skills, you can have it installed at the right location.

Universal Fitting Catalytic Converters: On the other hand, Universal fitting catalytic converters are not an OED component and will require additional modification or alterations to work well.

For this reason, a majority of universal fitting converters are quite cheaper than direct-fit converters.

However, the tools needed to fit in a universal catalytic converter are available at any professional mechanic workshop but be ready to pay installation costs.

Federal or CARB Converters:  The emission system of a catalytic converter is an aspect you must take into consideration before you make a purchasing investment.

The two widely accepted emission systems in the United States include CARB and Federal regulations.

The emission system should be indicated at the product detail or check the hood of your car.

The federal standard regulations for catalytic converters are consistent with the environmental protection agency responsible for setting carbon regulation.

On the other hand, CARB is an acronym for the California Air Resources Board responsible for setting carbon regulation in California.

They have stricter measures in place that’s why you don’t see many catalytic converters that are compliant with CARB.

To find out if your vehicle adheres to the CRAB regulation check to see if the catalytic converter has been stamped with a certification label.

This label will have a part number, manufacturing date, CARB number, and installation directions.

If your car was originally manufactured in California it should be CRAB compliant.

However, if your vehicle was manufactured or sold in the other 49 states of America there is a good chance that is not CARB compliant.

Catalytic Converter Grade

There are two main grades customers ought to be on the lookout for. According to folks At Magnaflow, these grades are Heavy Metal Grade OBDII and OEM grade OBDII.

The former conforms to federal emissions at the 0 and 1 tier while the latter conforms to CARB emission systems.

If your vehicle was manufactured before 1995 (pre-OBDII), Magnaflow suggests purchasing a Standard grade catalytic converter.

This also applies for pre-OBDII vehicles manufactured under the state of California.

What you may need to include with your purchase

There are several parts you may want to consider while you are shopping for the right catalytic replacement.

Oxygen sensors are very important for your car and should be replaced along with the catalytic converter if it is bad.

In practice, old oxygen sensors are a major problem and the reason for many error codes.

Replacing the oxygen sensors along with the catalytic converter will most times clear out all error codes.

Finally, you may want to look into the state of some exhaust parts.  The exhaust manifold, the exhaust headers, and the pipe are common parts that may need replacements.

Most Online Queries Regarding Best Aftermarket Catalytic Converter

 Q: What does a catalytic converter do?

Ans: A catalytic converter is a device that is used to convert harmful and toxic gases into less harmful gases produced by exhaust pipes.

Many converters are developed to meet stringent emission regulations so that they comply with environmental standards.

Q: What is the purpose of a Substrate?

Ans:  The substrate is the material that is used inside the shell of a converter.  Ideally, there are two types of substrates; Pelletized and Monolithic substrate.

The pelletized substrate consists of thousands of ceramic pellets used to convert harmful gases to CO2 and water.

Monolithic substrates are made in a honeycomb style to perform the same function as their pelletized counterparts.

Q: What then is a Catalyst?

Ans:  They are a metallic coating that is defined in Chemistry as substances that speed up a chemical reaction without taking part in that reaction itself.

Rhodium, platinum, and palladium are some popular catalysts used in catalytic converters.

Q: What is the difference between oxidation and two-way catalytic converters?

Ans:  There is practically no difference between oxidative catalytic converters and two-way catalytic converters.

Both types are used to control the emission of two harmful pollutants; carbon monoxide and some hydrocarbons.

Both catalytic converters work via the oxidation or burning of harmful gases in the presence of oxygen to produce CO2 and water vapor.

Q: What then are three-way catalytic converters?

Ans: Three-way catalytic converters are also known as redox converters or oxidation-reduction converters.

They perform the catalytic oxidation of two-way converters and besides help to reduce the levels of nitrous oxide.

Q: Is there a regulatory policy on the replacement of catalytic converters?

Ans: Yes, there is a regulatory policy on the installation of aftermarket catalytic converters.

This policy was enacted in 1966 by the Environmental protection agency and provides guidelines on the construction, and efficiency of catalytic converters.

Q:  What is referred to as the 1986 cut of rate?

Ans:  The latest EPA policy on catalytic converters outdates converters built before 1986 thus the sale and use of such converters violate the clean air policy act.

That date serves are the cut-off data as any converter built after that day is compliant with the clean air Act.

Q: Please, which catalytic converter should I use for my vehicle?

Ans:  Any vehicle using the wrong type of aftermarket converter may be in infringement of state policies on clean air.

It is important to consider the type of converter specific to your car model before making a purchase.

The best route to take is to seek the advice of professionals on the best converter to use for your car.

Q: Why does my converter go red hot when in use?

Ans:  One of the reasons why a catalytic converter can blow red hot is if there is a direct introduction of fuel to the system.

This shouldn’t be a problem with the converter itself but a problem with the fuel system.

You should immediately have it checked by a professional to avoid damaging consequences.

Q: What about clogging?

Ans: Clogging can occur when the catalytic converter is operated for too long under very high temperatures which can be facilitated by a faulty fuel or ignition system.

Clogged catalytic converters have had their substrate melted under intense heat. This can manifest itself as engine malfunction o sluggishness.

You should have the problem diagnosed as soon as possible.

Q:  Why do I have to remove my catalytic converter?

Ans: Converters are an important part of all vehicles. They help in fuel economy and the reduction of toxic gases to the atmosphere.

Therefore you should replace the converters if they have been damaged.

Q: What are the common signs of a failed catalytic converter?

Ans: Numerous situations can damage the catalytic converter. They could be damaged on the road when it hits a solid object or they can get contaminated.

If the wrong type of fuel is used in your vehicle, it may damage the catalytic converters.

For example, the use of lead-laden fuel or additives can clog up the system and damage the cat.

Subsequently, the monolith within the catalytic converter can be broken by accident or in aggressive contact with another object.

Overheating can also cause damage and we have rightly stated here that a problem with the fuel system can cause fuel to get into the catalytic converter.

This may lead to engine misfire and damage.

A faulty oxygen sensor may be the reason why the catalytic converter is bad. Oxygen sensors are responsible for sending the right message to the electronic unit in a bid to control the fuel and air mix.

If the sensors are bad, it may lead to excess fuel reaching the catalytic converter.

A leaking fuel injector system can also be the reason why your catalytic converter went bad. It also results in sending excess fuel to the cat.

Problems with the carburetor system can also contribute to a failed catalytic converter.

If the carburetor is worn out or defective you will need to arrange for a replacement or else risk running the engine as well.

Q: What will happen if my catalytic converter fails?

Ans: It’s very unlikely that the catalytic converter will abruptly fail altogether. It does take some time and when it does; your vehicle will break down.

You don’t want it to get to this stage before you take proactive measures to remedy the situation.

Q: Is it possible to unclog the catalytic converter?

Ans: Is possible to clean out a clogged catalytic converter but our experts’ advice against it.

You can try cleaning it out with water and a lacquer thinner. Let us know if you have any success with this approach.

Q: What are the common signs that my catalytic converter is failing and may need replacement?

Ans: The signs are undeniable. From sluggish engines, reduced acceleration, to very dark exhaust smoke, and the smell of sulfur.


In conclusion, we have reviewed 10 of the best catalytic converters in online stores.

From our analysis, Magnaflow seems to have some of the best variants of catalytic converters.

We’d strongly suggest you opt for this brand if you can because we are certain that you will get a quality converter from them.

Like e always advise, if you aren’t ready to make a purchasing decision, keep this review handy until you are ready. is a participant of the Amazon Affiliate program. We may earn a small commission if you purchase through our recommended links. More details.

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