2003 Audi A6 Catalytic Converters

Keep Your 2003 Audi A6 in Top Shape with Quality Catalytic Converters

Whether you’re repairing or upgrading your Catalytic Converter, using high-quality parts is key to keeping your 2003 Audi A6 looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Catalytic Converters. Whether you’re replacing a damaged part or enhancing your truck’s style and protection, you’ll find exactly what you need to get the job done right.

Top-Rated Catalytic Converters from Trusted Brands

Looking for a reliable Catalytic Converter? We’ve got you covered with options from brands you know and trust like Magnaflow. For example, Magnaflow Catalytic Converters start at just $178.99 with an average 4.1 star rating. With over 5 reviews and a solid 4 star average, you can shop with confidence knowing other Audi A6 owners approve.

Competitive Prices and Extensive Inventory

The average price for a 2003 Audi A6 Catalytic Converter at Advance Auto Parts is around $333.66, with a range that starts at $178.99 and goes up to $676.99. With 6 options in stock from one trusted brand, finding the right fit is easy. Popular picks like OEM Grade Universal Catalytic Converter – 2.25", Catalytic Converter: Universal, 2.5" T2 Front, and OEM Grade Universal Catalytic Converter – 2.25" start at just $188.99 and offer a great balance of form and function.

Explore Related Parts

While you’re upgrading or replacing your Catalytic Converter, don’t forget to check out other key components like Exhaust Gaskets. At Advance Auto Parts, we’re here to help you keep your 2003 Audi A6 in peak condition, inside and out.

Essential 2003 Audi A6 Catalytic Converters

MagnaFlow – Direct-Fit OEM Grade Catalytic Converter (Part No.51437)

Direct-Fit OEM Grade Catalytic Converter

from

$558.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 51437. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun” Body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun” Body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. Designed to fit the 2002-2004 Audi A6 Quattro and 2002-2004 Audi A6, this direct-fit catalytic converter also interchanges with OE parts 4B0 253 011 QX and 4B0 253 011 FX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

Walker – CalCat CARB Universal Catalytic Converter (Part No.81301)

CalCat CARB Universal Catalytic Converter

from

$401.99
Designed, tested and validated for assured compliance to meet CARB standards, Walker® CalCat® Universal Catalytic Converters are available for OBDII (1996 and newer) and non-OBD (1995 and older) vehicles.

Product Features:
  • SUPERIOR TECHNOLOGY — Optimal high technology washcoat formulated to deliver superior performance (as compared to EPA-compliant converters)
  • CONSISTENT PERFORMANCE — Utilizes a precise OE-style coating process to apply catalyst material to the substrate, providing consistent performance for assured emissions compliance
  • DURABLE — Features stainless-steel body with aluminized pipe and heat shields for durability
  • FLEXIBLE SOLUTION — Customizable design features expandable bushings for easy fitment and may require specialized fabrication and/or welding for installation
  • BUY WITH CONFIDENCE — Backed by Walker’s emissions and structural integrity warranty. Visit Walkerexhaust.com for details.
See More

MagnaFlow – California Universal Catalytic Converter – 2.00" (Part No.418004)

California Universal Catalytic Converter - 2.00"

from

$438.99
MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 418004 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – California Universal Catalytic Converter – 2.00" (Part No.444204)

California Universal Catalytic Converter - 2.00"

from

$428.99
MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 444204 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – OEM Grade Universal Catalytic Converter – 2.25" (Part No.51355)

OEM Grade Universal Catalytic Converter - 2.25"

from

$202.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51355 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – California Universal Catalytic Converter – 2.00" (Part No.408004)

California Universal Catalytic Converter - 2.00"

from

$298.99
MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 408004 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit OEM Grade Catalytic Converter (Part No.51438)

Direct-Fit OEM Grade Catalytic Converter

from

$676.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 51438. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun” Body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun” Body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. Designed to fit the 2002-2004 Audi A6 Quattro and 2002-2004 Audi A6, this direct-fit catalytic converter also interchanges with OE parts 4B0 253 012 QX and 4B0 253 012 FX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit California Grade Catalytic Converter (Part No.5461400)

Direct-Fit California Grade Catalytic Converter

from

$2472.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Direct-Fit Catalytic Converter 5461400. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun” Body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun” Body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2006-2009 Audi A6 and interchanges with OE part 4A0 253 058 EX. Avoid potential exhaust leaks by using the included gaskets to get a proper seal. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – OEM Grade Universal Catalytic Converter – 2.00" (Part No.51204)

OEM Grade Universal Catalytic Converter - 2.00"

from

$194.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51204 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit California Grade Catalytic Converter (Part No.5461003)

Direct-Fit California Grade Catalytic Converter

from

$2465.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Direct-Fit Catalytic Converter 5461003. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun” Body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun” Body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2006-2009 Audi A6 and interchanges with OE part 4A0 253 057 EX. Avoid potential exhaust leaks by using the included gaskets to get a proper seal. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

Walker – CalCat CARB Universal Catalytic Converter – 2" Inlet (ID) 2" Outlet (ID) (Part No.81101)

CalCat CARB Universal Catalytic Converter - 2" Inlet (ID) 2" Outlet (ID)

from

$459.99
Designed, tested and validated for assured compliance to meet CARB standards, Walker CalCat Universal Catalytic Converters are available for OBDII (1996 and newer) and non-OBD (1995 and older) vehicles.

Product Features:
  • CARB COMPLIANT – For use on OBDII vehicles, 1996 and newer and non-OBD 1995 and older. Legal for sale in CA, CO, NY & other states requiring CARB-compliant replacement converters. Consult your state’s aftermarket converter regulations.
  • SUPERIOR TECHNOLOGY – Optimal high technology wash coat formulated to deliver superior performance (as compared to EPA-compliant converters)
  • CONSISTENT PERFORMANCE – Utilizes a precise OE-style coating process to apply catalyst material to the substrate, providing consistent performance for assured emissions compliance
  • DURABLE – Features stainless-steel body with aluminized pipe and heat shields for durability
  • FLEXIBLE SOLUTION – Customizable design features expandable bushings for easy fitment and may require specialized fabrication and welding for installation
  • BUY WITH CONFIDENCE – Backed by Walker’s 50,000-mile/80,000-kilometer emissions and structural integrity limited warranty
See More

Walker – Ultra EPA Direct-Fit Catalytic Converter – 2" Outlet (OD) (Part No.55402)

Ultra EPA Direct-Fit Catalytic Converter - 2" Outlet (OD)

from

$782.99
Product Features:
  • EPA COMPLIANT – For use on OBDII vehicles, 1996 and newer. Not legal for sale or use in CA, CO & NY. Legal in ME on EPA Federal Emission Equipped Vehicles only. Consult your state’s aftermarket converter regulations for details.
  • DIRECT-FIT DESIGN – Direct-fit bolt-on replacement solution with OE-style hangers, brackets, routings and heat shields for easy installation that doesn’t require specialized fabrication and welding
  • KEEPS CHECK ENGINE LIGHT OFF FOR EMISSIONS CODES – OE-style high-technology wash coat and optimal precious metal load delivers required reduction in tailpipe emissions to match vehicle application
  • STRONG AND DURABLE – Features thick OE-style flanges, hangers and brackets for strength and durability
  • OE-STYLE DESIGN – Features aluminized heat shields when originally equipped, to match OE design, protecting the undercarriage from heat created by the converter
  • BUY WITH CONFIDENCE – Backed by Walker’s 25,000-mile/40,000-kilometer emissions and 50,000-mile/80,000-kilometer structural integrity limited warranty. Visit Walkerexhaust.com for details.
See More

MagnaFlow – HM Grade Universal Catalytic Converter – 2.25" (Part No.99205HM)

HM Grade Universal Catalytic Converter - 2.25"

from

$178.99
MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99205HM helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit OEM Grade Catalytic Converter (Part No.51964)

Direct-Fit OEM Grade Catalytic Converter

from

$1411.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 51964. DIY installation is easy with the proper tools, no cutting or welding required. With features including mandrel-bent tubing to eliminate flow restrictions and stainless steel construction to resist corrosion, you can have confidence in the quality of this catalytic converter. Using state-of-the-art 3D scanning systems in the design process, the MagnaFlow metrology department ensures this new part to fit and function like the original equipment. Designed to fit the 2000-2005 Volkswagen Passat, 2000-2001 Audi A6 Quattro, and more, this direct-fit catalytic converter also interchanges with OE parts 4B0 254 500 LX and 4B0 253 011 PX, among others. Avoid potential exhaust leaks by using the included gaskets to get a proper seal. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit California Grade Catalytic Converter (Part No.444327)

Direct-Fit California Grade Catalytic Converter

from

$1155.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Direct-Fit Catalytic Converter 444327. DIY installation is easy with the proper tools, no cutting or welding required. With features including mandrel-bent tubing to eliminate flow restrictions and stainless steel construction to resist corrosion, you can have confidence in the quality of this catalytic converter. Using state-of-the-art 3D scanning systems in the design process, the MagnaFlow metrology department ensures this new part to fit and function like the original equipment. Designed to fit the 2000-2005 Volkswagen Passat, 2000-2001 Audi A6 Quattro, and more, this direct-fit catalytic converter also interchanges with OE parts 4B0 254 550 LX and 4B0 253 012 PX, among others. Avoid potential exhaust leaks by using the included gaskets to get a proper seal. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit California Grade Catalytic Converter (Part No.444333)

Direct-Fit California Grade Catalytic Converter

from

$1316.99
Keep the check engine light off with MagnaFlow California Grade CARB Compliant Direct-Fit Catalytic Converter 444333. DIY installation is easy with the proper tools, no cutting or welding required. With features including mandrel-bent tubing to eliminate flow restrictions and stainless steel construction to resist corrosion, you can have confidence in the quality of this catalytic converter. Using state-of-the-art 3D scanning systems in the design process, the MagnaFlow metrology department ensures this new part to fit and function like the original equipment. Designed to fit the 2000-2005 Volkswagen Passat, 2000-2001 Audi A6 Quattro, and more, this direct-fit catalytic converter also interchanges with OE parts 4B0 254 500 LX and 4B0 253 011 PX, among others. Avoid potential exhaust leaks by using the included gaskets to get a proper seal. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

Walker – CalCat CARB Universal Catalytic Converter – 2" Inlet (ID) 2" Outlet (ID) (Part No.81660)

CalCat CARB Universal Catalytic Converter - 2" Inlet (ID) 2" Outlet (ID)

from

$509.99
Designed, tested and validated for assured compliance to meet CARB standards, Walker CalCat Universal Catalytic Converters are available for OBDII (1996 and newer) and non-OBD (1995 and older) vehicles.

Product Features:
  • CARB COMPLIANT – For use on OBDII vehicles, 1996 and newer and non-OBD 1995 and older. Legal for sale in CA, CO, NY & other states requiring CARB-compliant replacement converters. Consult your state’s aftermarket converter regulations.
  • SUPERIOR TECHNOLOGY – Optimal high technology wash coat formulated to deliver superior performance (as compared to EPA-compliant converters)
  • CONSISTENT PERFORMANCE – Utilizes a precise OE-style coating process to apply catalyst material to the substrate, providing consistent performance for assured emissions compliance
  • DURABLE – Features stainless-steel body with aluminized pipe and heat shields for durability
  • FLEXIBLE SOLUTION – Customizable design features expandable bushings for easy fitment and may require specialized fabrication and welding for installation
  • BUY WITH CONFIDENCE – Backed by Walker’s 50,000-mile/80,000-kilometer emissions and structural integrity limited warranty
See More

MagnaFlow – California Universal Catalytic Converter – 2.00" (Part No.448304)

California Universal Catalytic Converter - 2.00"

from

$718.99
MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 448304 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – California Universal Catalytic Converter – 2.00" (Part No.418054)

California Universal Catalytic Converter - 2.00"

from

$450.99
MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 418054 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed California Air Resource Board requirements, and has undergone additional testing to comply with CARB guidelines to allow for legal use in California and CARB restricted states, for the listed vehicles.

Product Features:
  • Your trusted source for CARB-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit HM Grade Catalytic Converter (Part No.24123)

Direct-Fit HM Grade Catalytic Converter

from

$717.99
Keep the check engine light off with MagnaFlow HM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 24123. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun” Body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun” Body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. This direct-fit catalytic converter is designed specifically for the 2006-2009 Audi A6 and interchanges with OE parts 4F0 254 555 NX and 4A0 253 058 EX, among others. Avoid potential exhaust leaks by using the included gaskets to get a proper seal. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – HM Grade Universal Catalytic Converter – 2.00" (Part No.99304HM)

HM Grade Universal Catalytic Converter - 2.00"

from

$188.99
MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99304HM helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – OEM Grade Universal Catalytic Converter – 2.25" (Part No.51205)

OEM Grade Universal Catalytic Converter - 2.25"

from

$194.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51205 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

Walker – Ultra EPA Universal Catalytic Converter – 2" Inlet (ID) 2" Outlet (ID) (Part No.93270)

Ultra EPA Universal Catalytic Converter - 2" Inlet (ID) 2" Outlet (ID)

from

$325.99
Product Features:
  • EPA COMPLIANT – For use on OBDII vehicles, 1996 and newer. Not legal for sale or use in CA, CO & NY. Legal in ME on EPA Federal Emission Equipped Vehicles only. Consult your state’s aftermarket converter regulations for details.
  • KEEPS CHECK ENGINE LIGHT OFF FOR EMISSIONS CODES – OE-style high-technology wash coat and optimal precious metal load delivers required reduction in tailpipe emissions to match vehicle application
  • DURABLE – Features stainless-steel body with aluminized pipe and heat shields for durability
  • FLEXIBLE SOLUTION – Customizable design features expandable bushings for easy fitment and may require specialized fabrication and welding for installation
  • OE-STYLE DESIGN – Features aluminized heat shields when originally equipped, to match OE design, protecting the undercarriage from heat created by the converter
  • BUY WITH CONFIDENCE – Backed by Walker’s 25,000-mile/40,000-kilometer emissions and 50,000-mile/80,000-kilometer structural integrity limited warranty. Visit Walkerexhaust.com for details.
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Walker – CalCat CARB Direct-Fit Catalytic Converter – 2" Outlet (OD) (Part No.81668)

CalCat CARB Direct-Fit Catalytic Converter - 2" Outlet (OD)

from

$1368.99
Designed, tested and validated for assured compliance to meet CARB standards, Walker CalCat Direct-Fit Catalytic Converters are available for OBDII (1996 and newer) and non-OBD (1995 and older) vehicles and delivers a precise OE-style fit.

Product Features:
  • CARB COMPLIANT – For use on OBDII vehicles, 1996 and newer and non-OBD 1995 and older. Legal for sale in CA, CO, NY & other states requiring CARB-compliant replacement converters. Consult your state’s aftermarket converter regulations.
  • DIRECT-FIT DESIGN – Direct-fit bolt-on replacement solution with OE-style hangers, brackets, routings and heat shields for easy installation that doesn’t require specialized fabrication or welding
  • SUPERIOR TECHNOLOGY – Optimal high technology wash coat formulated to deliver superior performance (as compared to EPA-compliant converters)
  • CONSISTENT PERFORMANCE – Utilizes a precise OE-style coating process to apply catalyst material to the substrate, providing consistent performance for assured emissions compliance
  • STRONG AND DURABLE – Features thick OE-style flanges, hangers and brackets for strength and stainless-steel body with aluminized pipe and heat shields for durability
  • BUY WITH CONFIDENCE – Backed by Walker’s 50,000-mile/80,000-kilometer emissions and structural integrity limited warranty
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Walker – Ultra EPA Universal Catalytic Converter – 2" Inlet (ID) 2" Outlet (ID) (Part No.93251)

Ultra EPA Universal Catalytic Converter - 2" Inlet (ID) 2" Outlet (ID)

from

$197.99
Product Features:
  • EPA COMPLIANT – For use on OBDII vehicles, 1996 and newer. Not legal for sale or use in CA, CO & NY. Legal in ME on EPA Federal Emission Equipped Vehicles only. Consult your state’s aftermarket converter regulations for details.
  • KEEPS CHECK ENGINE LIGHT OFF FOR EMISSIONS CODES – OE-style high-technology wash coat and optimal precious metal load delivers required reduction in tailpipe emissions to match vehicle application
  • DURABLE – Features stainless-steel body with aluminized pipe and heat shields for durability
  • FLEXIBLE SOLUTION – Customizable design features expandable bushings for easy fitment and may require specialized fabrication and welding for installation
  • OE-STYLE DESIGN – Features aluminized heat shields when originally equipped, to match OE design, protecting the undercarriage from heat created by the converter
  • BUY WITH CONFIDENCE – Backed by Walker’s 25,000-mile/40,000-kilometer emissions and 50,000-mile/80,000-kilometer structural integrity limited warranty. Visit Walkerexhaust.com for details.
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MagnaFlow – HM Grade Universal Catalytic Converter – 2.00" (Part No.99204HM)

HM Grade Universal Catalytic Converter - 2.00"

from

$179.99
MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99204HM helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
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Walker – CalCat Universal Catalytic Converter (Part No.80801)

CalCat Universal Catalytic Converter

from

$142.99
Walker an industry leader for import And domestic applications, offers Walker CalCat Universal Catalytic Converters, available for OBDII (1996 And newer) vehicles And Pre-OBD (1995 And older) vehicles, specifically formulated to comply with California Air Resource Board (CARB) regulations. Walker CalCat Catalytic Converters are legal for sale in the state of California, And any state complying with California regulations.

Product Features:
  • Legal for sale in the state of California, complies with C.A.R.B. regulations
  • Stainless steel body with aluminized pipe and heat shields for durability
  • Expandable bushings for custom installation requirements
  • Universal converter may require modification to complete installation
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MagnaFlow – OEM Grade Universal Catalytic Converter – 2.00" (Part No.51234)

OEM Grade Universal Catalytic Converter - 2.00"

from

$197.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51234 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
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Most Popular Catalytic Converters for 2003 Audi A6s

Enhance your 2003 Audi A6 with one of the 6 Catalytic Converters we have in stock, starting at just $178.99.

MagnaFlow – HM Grade Universal Catalytic Converter – 2.25" (Part No.99205HM)

HM Grade Universal Catalytic Converter - 2.25"

from

$178.99
MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99205HM helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – OEM Grade Universal Catalytic Converter – 2.25" (Part No.51355)

OEM Grade Universal Catalytic Converter - 2.25"

from

$202.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51355 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
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MagnaFlow – Catalytic Converter: Universal, 2.5" T2 Front (Part No.99355HM)

Catalytic Converter: Universal, 2.5" T2 Front

from

$188.99
MagnaFlow HM Grade Federal/EPA Compliant Universal Catalytic Converter 99355HM helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design (cutting and welding is required). With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – OEM Grade Universal Catalytic Converter – 2.25" (Part No.51205)

OEM Grade Universal Catalytic Converter - 2.25"

from

$194.99
MagnaFlow OEM Grade Federal/EPA Compliant Universal Catalytic Converter 51205 helps keep the check engine light off. Get the right fit for a wide array of vehicles thanks to the adaptable Universal design, cutting and welding is required. With highly corrosion resistant, stainless steel construction, you can have confidence in the quality of this catalytic converter. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Expertly formulated catalyst blend maximizes efficiency, ensuring optimal emissions control to keep your check engine light off
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Compact, lightweight construction enables installation in confined areas, welding is required
  • Durable 308 stainless steel MIG welds
See More

MagnaFlow – Direct-Fit OEM Grade Catalytic Converter (Part No.51438)

Direct-Fit OEM Grade Catalytic Converter

from

$676.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 51438. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun” Body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun” Body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. Designed to fit the 2002-2004 Audi A6 Quattro and 2002-2004 Audi A6, this direct-fit catalytic converter also interchanges with OE parts 4B0 253 012 QX and 4B0 253 012 FX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
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MagnaFlow – Direct-Fit OEM Grade Catalytic Converter (Part No.51437)

Direct-Fit OEM Grade Catalytic Converter

from

$558.99
Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 51437. With features including free-flowing mandrel-bent tubing and highly corrosion resistant stainless steel construction, easily install this spun” Body converter yourself using the proper tools, no cutting or welding required. MagnaFlow’s state-of-the-art metrology department uses the latest 3D scanning systems during research and development, so you can be confident that your new part will fit and function like the original equipment. By replicating the OE spun” Body design, the single laser fusion weld greatly reduces the possibility of a leak, and our compact, low-mass design also allows for greater thermal efficiency. Designed to fit the 2002-2004 Audi A6 Quattro and 2002-2004 Audi A6, this direct-fit catalytic converter also interchanges with OE parts 4B0 253 011 QX and 4B0 253 011 FX. This replacement part is designed to meet or exceed Federal emissions requirements set forth by the EPA, complying with legal standards for OBDII Federally registered vehicles with California or Federal/EPA Emission systems.

Product Features:
  • Your trusted source for EPA-compliant catalytic converters, providing assurance of genuine compliance while delivering quality that will last
  • Mandrel bent tubing retains OEM-like design and geometry, ensuring smooth exhaust flow for peak fuel economy and engine operation
  • High strength 16 gauge 409 stainless steel tubing for exceptional corrosion resistance and maximum service life
  • Expertly crafted to replicate OEM-like flow dynamics, maintaining factory performance and fuel efficiency
  • Simplifies installation with essential gaskets and hardware being included in the box
  • Durable 308 stainless steel MIG welds
See More

Top-Rated Catalytic Converter Brands For Your 2003 Audi A6

When it comes to finding the perfect Catalytic Converter for your 2003 Audi A6, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 1 trusted brands. We carry the most popular Catalytic Converter brands including Magnaflow, and more, all known for their exceptional customer ratings (average brand rating of 4.1 stars) and competitive prices, as low as $178.99. Purchasing a Catalytic Converter from us here at Advance Auto Parts is a smart move for both you and your 2003 Audi A6, providing peace of mind with parts that meet or exceed OEM standards.

Popular Magnaflow 2003 Audi A6 Catalytic Converters

If you’re looking for a top-quality Catalytic Converter for your 2003 Audi A6, Advance Auto Parts has exactly what you need with our selection of Magnaflow Catalytic Converters. We have 1 Magnaflow Catalytic Converters in stock for this fitment, all known for their durability and precision fit. With prices starting at just $178.99, you’ll find the perfect Catalytic Converter for your needs and budget. Magnaflow Catalytic Converters for the 2003 Audi A6 come highly rated, with over 5 customer reviews and an impressive average rating of 4.1 stars. Choosing a Magnaflow Catalytic Converter from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.
HM Grade Universal Catalytic Converter - 2.25"
from $178.99
(5)
HM Grade Universal Catalytic Converter – 2.25"
“needs to be cut to fit my application but worked great”

FAQs for 2003 Audi A6 Catalytic Converters

What are the best-selling Catalytic Converters for 2003 Audi A6s?

Out of 6 Catalytic Converters that fit 2003 Audi A6s, the following parts are the top sellers:

What’s the price range for 2003 Audi A6 Catalytic Converters?

The prices of Catalytic Converters for the 2003 Audi A6 range from $178.99 up to $676.99 for the most premium parts.

What is the average price of a Catalytic Converter for a 2003 Audi A6?

The average price for Catalytic Converters for the 2003 Audi A6 is $333.66. Keep in mind the variety of part types within our Catalytic Converter category, where you are likely to find a wide range of prices across a variety of parts and components.

Does Advance Auto Parts sell Catalytic Converters for other Audi A6 model years?

Yes, we carry Catalytic Converters for 16 model years of Audi A6s between 1995 and 2015. The following model years are the most popular for Catalytic Converter purchases: 2015, 2014, 2013, 2012, 2009, 2008, 2007, 2006, and 2004.

What are the cheapest Catalytic Converters for my 2003 Audi A6?

The cheapest 2003 Audi A6 Catalytic Converters we carry are:

Does Advance Auto Parts sell Catalytic Converters for any other 2003 Audi models?

Yes. We stock Catalytic Converters for 9 other popular 2003 Audi models. Some of the most popular are 2003 A4 Quattro Catalytic Converters, 2003 A4 Catalytic Converters, 2003 A6 Quattro Catalytic Converters, 2003 TT Quattro Catalytic Converters, and 2003 S6 Catalytic Converters.

What are the top-rated Catalytic Converters that fit the 2003 Audi A6?

The one 2003 Audi A6 Catalytic Converter we have in stock is the HM Grade Universal Catalytic Converter – 2.25". It is rated 4 stars and costs $178.99.

What types of Catalytic Converters do you sell for my 2003 Audi A6?

We currently have just 1 Catalytic Converter in stock for a 2003 Audi A6, and as of 11/2/25, it is a Catalytic Converter.

Can I get help with 2003 Audi A6 Catalytic Converter orders?

Contact our customer support team by chat or phone, through the help desk page, where you can find instant answers about Audi Catalytic Converters and more.

What is your return policy for Audi A6 Catalytic Converters?

Advance Auto Parts keeps returns simple. For new Audi A6 Catalytic Converters and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.