AP Exhaust®Verified to fit 67 vehicles
| Vehicle | Trim | Engine | Notes |
|---|---|---|---|
| 2011 Audi A5 Quattro | — | L4 2.0L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2011 Cadillac DTS | — | V8 4.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Includes Resonator|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2010 Buick LaCrosse | — | V6 3.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2010 Cadillac DTS | — | V8 4.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Includes Resonator|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2009 Cadillac DTS | — | V8 4.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Includes Resonator|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2009 Cadillac SRXRight | — | V6 3.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2008 Cadillac CTSRight | — | V6 3.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2008 Cadillac DTS | — | V8 4.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Includes Resonator|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2007 Cadillac CTSLeft | — | V6 3.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2007 Cadillac DTS | — | V8 4.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Includes Resonator|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2006 Cadillac CTSLeft | — | V6 3.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2006 Cadillac DTS | — | V8 4.6L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Includes Resonator|The O.E. system must be cut off 16" behind the rear resonator weld.|Federal and California Emissions |
| 2005 Buick LeSabre | — | V6 3.8L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Use w/OE Pipe|Includes Resonator|Federal and California Emissions |
| 2005 Buick Park Avenue | — | V6 3.8L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|Use w/OE Pipe|Includes Resonator|Federal and California Emissions |
| 2005 Buick Rendezvous | — | V6 3.4L | Note: Not for sale or use on vehicles licensed in the states of CA, CO, ME, and NY. Restrictions may apply in other states. Check with your state authority for details.|(Use w/ OE Pipe, Includes Resonator)|Direct fit converter may require resizing, cutting or bushing.|Cut O.E. extension pipe as necessary for installation.|Federal and California Emissions |
WARNING: Handling passenger or off-highway motor vehicle parts can expose you to chemicals such as phthalates and lead, known to the State of California to cause cancer and reproductive harm. Service the vehicle in a well-ventilated area, wear gloves, and wash your hands. See www.P65Warnings.ca.gov/motor-vehicle-parts
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If a part we confirmed for your vehicle does not fit, we cover the return shipping and refund you in full. That is the fitment guarantee.
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Nobody likes buying a part that turns out to be wrong. So if it doesn't fit, send it back for a full refund at no cost to you — return shipping is on us — and we'll help you get the right one.
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Every part is covered for 24 months. Many brands add their own manufacturer warranty on top.
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AP Exhaust Stainless Steel Exhaust Pipe Flange Gasket 645979
Guaranteed fit or free return
AP Exhaust Stainless Steel Exhaust Pipe Flange Gasket 645979
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About This Catalytic Converter
This AP Exhaust automotive component is engineered to meet or exceed OEM specifications for reliable performance and long service life.
Key Features
- Meets or exceeds OEM specifications
- Direct-fit replacement design
- Rigorously tested for durability
- Professional-grade construction
- Backed by manufacturer warranty
Signs This Part Needs Replacement
- •Unusual noises from the component area
- •Decreased vehicle performance
- •Warning lights on dashboard
- •Visible wear or damage
- •Failed vehicle inspection
AP Exhaust
Trusted Automotive Brand
AP Exhaust is a trusted manufacturer of quality automotive parts.
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The AP Exhaust Catalytic Converter (645979) is sold by AutoBuffy. UPC 085337244112. In stock and ships free.
About This Product
Catalytic Converter
The AP Exhaust Catalytic Converter (645979) is sold by AutoBuffy. UPC 085337244112. In stock and ships free.
This AP Exhaust automotive component is engineered to meet or exceed OEM specifications for reliable performance and long service life.
Key Features
- Meets or exceeds OEM specifications
- Direct-fit replacement design
- Rigorously tested for durability
- Professional-grade construction
- Backed by manufacturer warranty
Signs This Part Needs Replacement
- Unusual noises from the component area
- Decreased vehicle performance
- Warning lights on dashboard
- Visible wear or damage
- Failed vehicle inspection
Brand-first. Fitment-obsessed.
We only sell brands automakers trust, and we double-check the fit on every listing.
Top curated brands only
The brands automakers put on the car.
Obsessed with fitment
Year, make, model, trim, engine, plus the fine print.
Search any part number
Your old part, a competitor, or the dealer #. We confirm the match.
Shop owner? Get BuffyPro business pricing
Fitment Obsessed
Every part checked against your exact year, make, model, trim, and engine.
Wrong Fit? On Us.
Free return shipping, no restocking fee — the fitment guarantee.
Brands OEMs Trust
The names automakers actually put on the car.
Millions of Parts, One Promise
If we say it fits, it fits.