2009-2011 Audi S6 Fender Guide: Wider Flares, Aluminum Corrosion, and A6 Incompatibility
This definitive guide covers the unique, wider aluminum fenders on the 2009-2011 Audi S6, including how to spot damage and avoid buying the wrong part.
- The 2009-2011 S6 front fender is wider than a standard A6 fender and they are not interchangeable.
- Fenders are made of aluminum, which will not rust but can suffer from paint bubbling and white, powdery corrosion that requires special repair methods.
- When buying used, prioritize verifying it is a true S6 fender and inspect carefully for hidden body filler or signs of corrosion.
- Replacement is a moderate-difficulty job that requires removing the wheel, fender liner, and front bumper cover.
Symptoms of a Damaged Fender
As a body panel, fender "failure" is typically visible damage from impacts or corrosion. Here’s what to look for:
- Dents, Dings, and Creases: The most common issue is physical damage from parking lot incidents, road debris, or minor collisions. Because the fender is aluminum, dent repair requires specialized tools and techniques.
- Paint Bubbling and Corrosion: The S6 fender is aluminum and won't get red rust, but it can corrode. Look for paint bubbling or blistering, especially along edges or near mounting points where it may contact steel components. This is often a sign of filiform corrosion, which looks like thin, thread-like filaments under the paint, or galvanic corrosion.
- White, Powdery Residue: Galvanic corrosion, which occurs when aluminum is in contact with a different metal (like steel bolts) and an electrolyte (like road salt), appears as a white, chalky powder. Check carefully around all bolt holes and seams.
- Poor Panel Gaps: Uneven gaps between the fender, hood, A-pillar, and front door can indicate a previous low-quality repair or underlying structural damage from an accident.
- Tire Rubbing: In cases of severe damage, a bent or pushed-in fender can make contact with the tire, especially during turns or suspension compression. This is a safety issue that should be addressed immediately.
Compatibility Warning: The 2009-2011 Audi S6 front fenders are NOT the same as the fenders on a standard Audi A6 of the same year. The S6 fenders are visibly wider and more flared to accommodate the S6's performance-oriented stance. An A6 fender will not fit correctly or cover the S6's wheel and tire setup properly.
Buying a Used 2009-2011 S6 Fender: Inspection Guide
A used OEM fender is often the best choice, offering perfect factory fitment and the correct aluminum material, which can be superior to a new aftermarket part made of steel. However, careful inspection is critical.
How to Verify the Part
- Confirm it's for an S6: Ask the seller to confirm the donor vehicle was an S6, not an A6. The wider flare is the key visual difference. If you can compare it to your existing fender, the difference will be obvious.
- Check the Part Number: Look for a stamped or stickered part number on the inside surface. The OEM part number for the front left (driver's side) fender is 4F0-821-103-G.
- Material Check: A magnet will not stick to the aluminum S6 fender. If it sticks, you are looking at a cheaper steel aftermarket part.
Physical Inspection Checklist
- Check for Previous Repairs: Look at the back side of the fender. Do you see any signs of sanding, body filler (often a different texture or color), or non-factory welds? Run your hand along the surface to feel for inconsistencies. A paint depth gauge is the best tool for finding hidden bodywork.
- Inspect for Corrosion: Scrutinize the edges, mounting holes, and the lower section near the door for any paint bubbling or white powder. This kind of damage can be costly to repair properly.
- Examine All Mounting Points: Check every hole and tab where the fender bolts to the car. Look for cracks, stress marks, or elongated holes, which can make proper alignment impossible.
- Assess the Paint: Finding a used fender in the same color can be a huge cost savings. However, be aware that sun exposure and age mean the paint may not be a perfect match to your car. Expect to at least have a body shop blend the new panel's paint into the adjacent door and hood for a seamless look.
Known Issues, Recalls, and TSBs
There are no specific recalls or Technical Service Bulletins (TSBs) issued by the NHTSA for the fenders on the 2009-2011 Audi S6. The primary known issue is the potential for aluminum corrosion if the paint is chipped or scratched, particularly in regions that use road salt.
While not related to the fender, owners should be aware that this vehicle generation has several prominent recalls for faulty Takata airbag inflators. It is highly recommended to check your vehicle's VIN on the NHTSA website to ensure all safety recalls have been performed.
Replacement Difficulty and Cost
Replacing an S6 fender is more complex than simply unbolting it. The process typically requires removing the front wheel and fender liner, and at least partially removing the front bumper cover and headlight to access all the mounting bolts.
- Installation Difficulty: 3/5 (Moderate)
- DIY Feasible: Yes, for mechanically experienced individuals.
- Special Tools: Trim removal tools, Torx and socket sets. Proper panel alignment requires patience.
Cost Breakdown
Prices can vary based on location and supplier. Painting and installation are significant additional costs.
| Part/Service | Estimated Cost |
|---|---|
| New OEM Fender (Unpainted) | $750 - $1,100 |
| New Aftermarket Fender (Material may vary) | $200 - $550 |
| Used OEM Fender | $250 - $450 |
| Shop Labor: Installation | $150 - $300 |
| Shop Labor: Painting & Blending | $500 - $1,200+ |
Pro Tip: Due to the high cost of professional painting, finding a clean, used OEM fender in the correct factory color can save you hundreds of dollars, even if it's not a perfect 10/10 match. For a daily driver, this is often the most economical solution.
Frequently Asked Questions (FAQ)
Is the 2009-2011 Audi S6 fender made of steel or aluminum?
The front fenders on the C6-generation Audi S6 are made of aluminum to reduce weight. This requires special repair procedures for dents and corrosion, and not all body shops are equipped to work on aluminum panels.
Will a fender from an Audi A6 fit my S6?
No. The front fenders on an S6 are wider and more flared than those on a standard A6 to accommodate the S6's wider stance. You must use a fender specifically designed for the S6 model.
Do I need to remove the front bumper to replace the fender?
Yes, in most cases you will need to at least loosen and pull away the side of the front bumper cover to access the bolts that secure the fender. Many procedures recommend full removal of the bumper cover for easier access.
If I buy a used fender in the same color, will it match my car perfectly?
It is unlikely to be a perfect match. Paint fades and weathers over time, so a fender from a donor car will have a slightly different shade than your vehicle. For a perfect, invisible repair, a body shop will need to blend the paint from the replacement fender onto the adjacent hood and door.
Technical Specifications
OEM Part Numbers: 4F0-821-103-G 4F0821103G
Material: Aluminum
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Audi S6: