Audi S6 (2013-2022) Serpentine Belt and Tensioner Guide
Understand the critical differences in the serpentine belt system between the C7 and C8 generation Audi S6.
- Identify your S6 engine: 2013-2018 models have a 4.0L V8, while 2019-2022 models have a 2.9L V6. They use different parts.
- A squealing noise often points to a failing tensioner, not just the belt. It's best to replace them together.
- Do not drive if the belt has failed. You will lose cooling and charging, risking severe engine damage.
- Top aftermarket brands like Continental, Gates, and Dayco offer OEM-quality or better performance for this part.
Engine-Specific Information Is Critical
The 2013-2022 year range for the Audi S6 covers two distinct generations with different engines. It is essential to identify your vehicle's specific engine before purchasing parts.
- 2013-2018 (C7 Generation): These models are equipped with a 4.0L twin-turbo V8 engine.
- 2019-2022 (C8 Generation): These models in North America use a 2.9L twin-turbo V6 engine.
These engines use different serpentine belts, tensioners, and have unique service procedures. This guide will cover common symptoms and parts for both generations.
Symptoms of a Failing Serpentine Belt or Tensioner
A failing serpentine belt or tensioner will give you clear warning signs. 🎬 Watch this video to see common symptoms of belt failure. Ignoring them can lead to being stranded if the belt breaks.
- Squealing or Chirping Noises: This is the most common symptom. A high-pitched squeal, especially on cold starts or when accelerating, often points to a worn belt or a failing tensioner that can no longer keep proper pressure.
- Visible Wear: Look at the belt. Cracks, fraying, missing ribs, or a shiny, glazed surface are all signs it needs to be replaced.
- Battery Warning Light: If the belt is slipping, it cannot turn the alternator properly. This prevents the battery from charging, which will trigger the battery light on your dashboard.
- Engine Overheating: The belt drives the water pump. A slipping or broken belt means the water pump isn't circulating coolant, causing the engine to overheat quickly.
- Loss of Power Steering or A/C: Since the belt powers these accessories, you might notice the steering becomes heavy or the A/C stops blowing cold air if the belt is failing.
Known Issue: Belt Tensioner Failure
For the 4.0T V8 engine in particular, squealing noises are frequently caused by a failing belt tensioner, not just the belt itself. The tensioner is a spring-loaded part that keeps the belt tight. When it weakens, it can't maintain pressure, causing the belt to slip and squeal. It is highly recommended to inspect the tensioner and idler pulleys when replacing the belt. An Audi Technical Service Bulletin (TSB) for the C8 models also addresses belt noise, recommending replacement of the belt and tensioner if noise is present.
Choosing the Right Aftermarket Serpentine Belt
For your Audi S6, the quality of aftermarket serpentine belts is generally very high, and in many cases, the aftermarket manufacturer is also the original equipment (OEM) supplier. Continental, Gates, and Dayco are all reputable brands.
🎬 Check out this detailed buyer's guide for top serpentine belts.- Continental: Often considered a top choice for European vehicles and is frequently the OEM supplier. Their belts are known for quiet operation and OEM-level quality.
- Gates: A highly respected brand in the aftermarket with a reputation for durability and quality that meets or exceeds OEM specifications.
- Dayco: Another major OEM supplier, known for innovative designs. While a quality brand, some mechanics note their belts can be stiffer and more prone to noise if not installed perfectly. 🎬 See a comparison between Continental, Gates, and Dayco belt brands.
Pro Tip: Replace as a Kit
Experienced mechanics recommend replacing the serpentine belt, tensioner, and any idler pulleys at the same time. The labor involved to access these parts is significant, and these components wear out at a similar rate. Replacing only the belt may lead to a premature failure if an old tensioner or pulley seizes, which can shred your new belt and leave you stranded.
Cost of Serpentine Belt Replacement for Audi S6
| Part/Service | Estimated Cost |
|---|---|
| New Aftermarket Serpentine Belt | $21 - $60 |
| New OEM Serpentine Belt | $48 - $79 |
| Shop Labor Cost | $186 - $273 |
| Total Professional Replacement | $234 - $352 |
Frequently Asked Questions (FAQ)
When should I replace my S6's serpentine belt?
Most serpentine belts are designed to last between 60,000 and 100,000 miles. However, you should inspect it regularly during oil changes. Replace it immediately if you notice any symptoms of wear or failure, regardless of mileage.
Is the OEM Audi belt better than aftermarket?
Not necessarily. Brands like Continental are often the direct supplier to Audi, so you can get the same quality part without the dealership markup. Gates and Dayco are also excellent alternatives that meet or exceed OEM standards.
What happens if my serpentine belt breaks while driving?
If the belt breaks, your engine will lose power to the alternator, water pump, and power steering. The battery will stop charging, the engine will quickly overheat, and steering will become very difficult. You should pull over immediately and safely to avoid catastrophic engine damage.
Are there any recalls on the Audi S6 serpentine belt?
There are no specific recalls for the serpentine belt itself on 2013-2022 Audi S6 models. However, Audi has issued Technical Service Bulletins (TSBs) related to belt noise and the 48V starter-generator system on newer models, which is driven by the belt. There are several other recalls for these vehicles, but they are unrelated to the belt drive system.
Helpful Videos
Technical Specifications
OEM Part Numbers: 079903137AJ 079903137AR
The key difference is the engine type. The C7 generation (2013-2018) uses a 4.0T V8, while the C8 generation (2019-2022) uses a 2.9T V6. Belts are not interchangeable.
We Have This Part in Stock
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:
- 🎬 Helpful Videos
- 🛍️ Shop This Part
- Engine-Specific Information Is Critical
- Symptoms of a Failing Serpentine Belt or Tensioner
- Known Issue: Belt Tensioner Failure
- Choosing the Right Aftermarket Serpentine Belt
- Pro Tip: Replace as a Kit
- Cost of Serpentine Belt Replacement for Audi S6
- Frequently Asked Questions (FAQ)
- 🎟️ Get 5% Off