SKU: 3984084406

Catalytic Converter for 2000-2004 Audi A6 Quattro 4.2L MagnaFlow 51664

Sale price$282.60 Regular price$314.00
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Ships within 48 hours · Estimated delivery Jul 17 - Jul 22

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Description

Catalytic Converter for 2000-2004 Audi A6 Quattro 4.2L MagnaFlow 51664Overview: Keep the check engine light off with MagnaFlow OEM Grade Federal EPA Compliant Direct Fit Catalytic Converter 51664. 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

Overview:

Keep the check engine light off with MagnaFlow OEM Grade Federal/EPA Compliant Direct-Fit Catalytic Converter 51664. 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 2000-2004 Audi A6 Quattro and 2002-2003 Audi S6, this direct-fit catalytic converter also interchanges with OE parts 4B3 254 550 GX, 4B3 253 058 BX, among others.

Note : Not For Sale in California

Interchange:

Brand  Interchange Part Number
Audi 4B3 253 058 AX
Audi 4B3 253 058 BX
Audi 4B3 254 550 CX
Audi 4B3 254 550 GX
Audi 4B3253058AX
Audi 4B3253058BX
Audi 4B3254550CX
Audi 4B3254550GX
Audi 4B3 253 058 AX
Audi 4B3 253 058 BX
Audi 4B3 254 550 CX
Audi 4B3 254 550 GX
Audi 4B3253058AX
Audi 4B3253058BX
Audi 4B3254550CX
Audi 4B3254550GX

Application:

Year Make Model Submodel Engine Size
2000 - 2004 Audi A6 Quattro 4.2L/V8
2002 - 2003 Audi S6 4.2L/V8

Specs:

Oxygen Sensor Location Pre and Post Converter
Overall Length (In.) 51
Substrate Material Ceramic
Air Tube Adaptable No
Converter Quantity 1
Inlet Attachment Bolt-On
Material Stainless Steel
Outlet Attachment Clamp-On
Finish Stainless Steel
Series OEM Grade
Main Piping Diameter (In.) 2.25
Subtitle Federal / EPA Compliant
Title OEM Grade Direct-Fit
Type Direct-Fit
Body Material Stainless Steel
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 3984084406

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K
Verified Purchase
Ken Hill
Lowell, US
★★★★★ 5
helped treat my sore neck
Color: White-cooling Basic, Size: Camping Pillow(Pack of 1)
This pillow — after dialing in the right amount of shredded foam — has greatly helped my sore neck. Initially, I had to remove some foam. Then I gradually added foam until it reached optimum comfort and support. It is also CPAP-friendly — especially when I position my head near the pillow's edge. (I am a left-side sleeper.) I like the travel size because I use a bulky hugging pillow to ease stress on my shoulder and elbow. That makes my side of the bed feel cramped if using a larger head pillow. A smaller pillow is easy to flip end-to-end in the middle of the night. I have spent lots of money on pillows over the years, but this is the best I've ever had for relieving [1] neck pain and [2] CPAP mask seal problems. Very comfortable, supportive, and affordable. I did not notice any unpleasant smell — and I am usually sensitive to that kind of thing. Would highly recommend.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 7, 2026
M
Verified Purchase
Molly Farrell
Louisville, US
★★★★★ 5
Love them!
Color: White-cooling Basic, Size: Queen(Pack of 2)
Love them! After 10 years with our MyPillows, they finally lost their fluff. The reviews I read of the MyPillows of today were not good; they didn’t have as much filling as they used to. These pillows remind me of how fluffy our new MyPillows were 10 years ago!! You sink right into them and can mush them however and they stay. These are way cheaper than the Coop and it’s the same concept; add or remove the filling as needed. The cooling side is a huge plus too! You won’t be disappointed with these pillows!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 22, 2026
S
Verified Purchase
2021 self improvement challenge
Massapequa, US
★★★★★ 5
Actually cooling and comfortable.
Color: Royal Blue, Size: King
Incredible cases. Soft, super comfortable and actually cooling as claimed. Highly recommended. Love these!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
J
Verified Purchase
Janet L. Dolbow
Lowell, US
★★★★★ 5
Cool
Color: Pink, Size: Standard
Cooling pillowcases work well, don’t wake up sweaty anymore. Very happy with them. Love the material, comfort and softness!
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Reviewed in the United States on June 7, 2026
M
Verified Purchase
md
Massapequa, US
★★★★★ 5
COOL Pillowcases Worth Buying
Color: Champagne, Size: Queen
I bought these to try out, and I was shocked to find they worked out better than my silk pillowcases. I have atopic dermatitis, and I need a pillowcase that doesn't irritate my skin. I also am having hot flashes and need something cool on my face. These pillowcases are perfect for both my conditions. I plan to buy more in different colors. My sons and husband also like it since they are always hot.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 30, 2026

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