What Kind of Battery Does a 2008 Audi A4 Take?
A 2008 Audi A4 typically uses a Group 48 (also referred to as H6 or L3) 12‑volt AGM or flooded lead‑acid battery, with around 70–80 Ah capacity and 680–800 CCA, but exact specs depend on engine (2.0T, 3.2) and whether the car has many electrical options or cold‑weather use. In practice, most owners replace it with a high‑quality Group 48/H6 battery that meets or exceeds OEM cold‑cranking amps and reserve capacity.
Contents
Understanding the 2008 Audi A4 Battery Specification
The 2008 Audi A4 sits at the point where European carmakers were increasing electrical demands: more electronics, more safety systems, and, in some trims, higher‑output alternators. The battery is a critical piece of that system, and using the correct group size and performance rating is key for reliable starting and stable electrical performance.
Factory-Style Battery Type and Group Size
From the factory, most 2008 Audi A4 models were supplied with a European‑spec, maintenance‑free 12‑volt lead‑acid battery in the “H6” size, which matches North American Group 48 and the European “L3” form factor. This group size determines the physical dimensions, terminal placement, and fitment under the hood.
The following list outlines the typical original-equipment style specifications for a 2008 Audi A4 battery.
- Battery group size: Group 48 / H6 / L3
- Voltage: 12 V nominal
- Capacity (Ah): Typically around 70–80 Ah
- Cold Cranking Amps (CCA): Generally in the 680–800 CCA range
- Reserve capacity (RC): Commonly around 120+ minutes (varies by brand)
- Polarity: Standard left‑positive layout for Group 48
- Construction: Maintenance‑free lead‑acid, often AGM in premium replacements
These baseline specifications provide a framework: as long as the replacement battery respects the Group 48/H6 size and meets or exceeds Audi’s original CCA and capacity values, it will physically fit and properly support the A4’s electrical system.
AGM vs. Conventional Flooded Lead-Acid
The 2008 Audi A4 did not universally require AGM (Absorbent Glass Mat) batteries from the factory, but high‑spec or cold‑climate cars often benefit from them. Today, many premium aftermarket options for German sedans are AGM due to better performance and durability.
The list below compares AGM and standard flooded batteries in the context of the 2008 A4.
- AGM (Absorbent Glass Mat):
- Better tolerance of deep discharge and heavy accessory loads
- Improved resistance to vibration and heat
- Lower self‑discharge when parked for long periods
- Typically higher price but longer service life when properly charged
- Flooded lead‑acid (conventional):
- Lower upfront cost and widely available
- Acceptable for mild climates and lighter electrical loads
- More sensitive to repeated deep discharges
- Can vent slightly more, making proper ventilation important
For a 2008 Audi A4 that sees regular use and has typical electrical equipment, both AGM and high‑quality flooded Group 48 batteries will work; however, AGM is generally recommended if budget allows, especially for vehicles with many accessories or frequent short trips.
Fitment Differences by Engine and Trim
Within the 2008 Audi A4 range—primarily the 2.0T and 3.2 V6 variants—battery group size remains broadly consistent, but recommended capacity and CCA can vary slightly based on engine and equipment packages. Audi typically selects higher‑output batteries for larger engines and more heavily optioned cars.
2.0T vs. 3.2 and Quattro Models
Although both main engines in the 2008 A4 lineup can use Group 48/H6, the V6 and Quattro models are more demanding electrically, especially in cold climates or when fitted with options such as heated seats, advanced audio, and navigation.
The following list summarizes typical guidance by configuration.
- A4 2.0T FrontTrak (front‑wheel drive):
- Group 48/H6 battery
- CCA commonly toward the lower end of the 680–800 CCA range is acceptable
- Standard or mid‑range capacity is usually sufficient in temperate climates
- A4 2.0T Quattro and 3.2 Quattro:
- Still Group 48/H6, no size change
- Prefer a battery toward the upper end of the 700–800+ CCA range
- Higher reserve capacity is beneficial for added electrical loads
Engine and drivetrain do not radically alter the physical battery size, but choosing a higher‑capacity, higher‑CCA unit for Quattro or V6 models helps ensure strong cold‑weather cranking and resilience under heavy accessory use.
Key Specifications to Match When Buying a Replacement
Replacing the battery in a 2008 Audi A4 is not just a matter of picking something that fits in the tray; certain electrical specifications ensure reliable cold starts, prevent computer glitches, and support all accessories.
Core Numbers: CCA, Ah, and Reserve Capacity
Battery labels present several numbers, but three are particularly relevant to the 2008 A4: CCA (Cold Cranking Amps), Ah (Amp‑hours), and RC (Reserve Capacity). Matching or slightly exceeding factory specs is generally recommended.
The list below outlines the main values to look for on a replacement battery label.
- Cold Cranking Amps (CCA):
- Target: about 680–800+ CCA
- Higher CCA helps with winter starting and aging electrical systems
- Amp‑hour rating (Ah):
- Typical range: around 70–80 Ah
- Higher Ah means more stored energy for electronics when the engine is off
- Reserve Capacity (RC):
- Often 120 minutes or more for quality Group 48 units
- Indicates how long the battery can supply power if the alternator fails
- Group Size / H‑Code:
- Must be Group 48 / H6 / L3 for proper fitment and terminal alignment
Choosing a battery that matches or slightly surpasses these specifications gives the 2008 A4 a comfortable margin for age‑related wear, seasonal temperature swings, and occasional higher electrical loads.
Installation Considerations for the 2008 Audi A4
While swapping a battery on a 2008 A4 is within reach for a careful DIY owner, the car’s electronics, radio settings, and window calibration can be affected by loss of power. Planning the installation reduces the risk of issues after the change.
Physical Access, Hold-Down, and Venting
The battery in the 2008 A4 is mounted in the engine bay, typically on the right‑hand side (passenger side in LHD markets), with a hold‑down clamp and a cover. Proper fitment is critical for safety and longevity.
The list below describes the main installation steps and points to check.
- Access and removal:
- Remove the plastic battery cover and inspect the hold‑down bracket
- Disconnect negative (–) terminal first, then positive (+)
- Unbolt the hold‑down and carefully lift the battery straight up
- Check the battery tray and wiring:
- Clean corrosion from tray and terminals if present
- Confirm cables and terminals are intact and tight
- Install the new Group 48/H6:
- Ensure the vent port and any vent tube (if present) are connected
- Secure the hold‑down so the battery cannot move under braking
- Reconnect positive (+) terminal first, then negative (–)
- Final checks:
- Verify that the battery sits flat and the cover fits correctly
- Start the engine and check for warning lights or odd behavior
Following these steps helps ensure a secure physical installation and good electrical contact, which in turn supports stable voltage to the A4’s control modules and accessories.
Electronics, Coding, and System Resets
The 2008 Audi A4 is early enough that full “battery registration” (as seen on later Audis and BMWs) is generally not as strict, but the car’s control units still benefit from stable voltage and, in some cases, proper coding when changing key components.
The list below covers what owners commonly experience after a battery swap and how to handle it.
- Window and sunroof initialization:
- One‑touch up/down may stop working temporarily
- Re‑initialize by holding the switch fully up and down for a few seconds
- Radio and clock settings:
- Radio presets and clock may reset and require manual re‑entry
- In some cases, a radio code may be needed if the car is very original
- Steering angle sensor / ESP light:
- A steering or ESP warning light can appear briefly
- Turning the steering wheel lock‑to‑lock with the engine running often clears it
- Battery monitoring:
- The 2008 A4 is less sensitive than newer models, but if advanced coding tools are available, some technicians will log the new battery data in diagnostic software
While most owners can replace the battery without specialized coding, being prepared for minor resets and warning lights prevents unnecessary concern after installation.
Selecting a Brand and Warranty
Once the correct group size and specifications are known, choosing a reputable brand with solid warranty coverage is the final step. Not all Group 48 batteries are equal in quality or longevity.
What to Look for in a Replacement Battery Brand
Brand reputation and warranty terms often reflect underlying quality and consistency. For a 2008 A4—which many owners keep on the road well past 150,000 miles—a robust battery is worth the incremental cost.
The list below outlines factors to consider when picking a specific battery model.
- Warranty length and coverage:
- Look for at least a 3‑year free replacement period on AGM units
- Pro‑rated coverage beyond that can be useful for high‑mileage cars
- Reputation and reviews:
- Prioritize brands known for European‑car fitments and consistent CCA performance
- Check owner feedback specific to Group 48/H6 for real‑world durability
- Freshness of stock:
- Inspect the manufacturing date code; newer is better, ideally less than 6–9 months old
- A battery that sat on a shelf for years may deliver reduced life
- AGM vs. flooded choice:
- Choose AGM if you value longer life, better cold performance, and deeper‑cycle tolerance
- Choose quality flooded if budget is tight but you still want OEM‑level specs
Evaluating these factors alongside the correct Group 48/H6 form factor helps ensure the replacement battery will serve the 2008 A4 reliably for years, reducing the risk of no‑start situations and electrical issues.
Summary
A 2008 Audi A4 almost universally uses a 12‑volt Group 48 (H6/L3) battery, with typical ratings in the 70–80 Ah and 680–800 CCA range. Both 2.0T and 3.2 models share this physical size, though higher‑output batteries are better for Quattro or heavily optioned cars. Modern best practice favors a high‑quality AGM Group 48/H6 unit, but a premium flooded battery with equivalent specifications is also acceptable. Ensuring the correct group size, adequate CCA and capacity, proper installation, and a reputable brand with a solid warranty will give the 2008 A4 the electrical stability it needs for dependable daily use.
What size battery is in the 2009 Audi A4?
The 2009 Audi A4 battery size is typically Group 49 (also known as H8) for the 3.2L V6, or Group 94R (also known as H7) for the 2.0L 4-cylinder engine, but it’s best to verify the exact group size and specs (like cold cranking amps) with the specific vehicle’s documentation or a battery finder, as some options may differ based on factory specifications.
2009 Audi A4 battery sizes
- For the 3.2L V6 engine: Group 49 (H8) is a common fit. These batteries are often ~850 cold cranking amps and have a length of about 14 inches.
- For the 2.0L 4-cylinder engine: Group 94R (H7) is a common fit, often with around 750 cold cranking amps.
Important considerations
- Check your vehicle’s specific requirements: Because Audi used different batteries depending on the specific model and options, it’s crucial to confirm the correct battery size for your vehicle. Using a vehicle-specific battery finder tool or checking your owner’s manual is the most reliable method.
- Professional installation: Some batteries, particularly those in the Group 49 size, can be difficult to install and may require professional assistance. It’s also necessary to reset the vehicle’s computer system after a battery replacement to ensure proper function.
- Battery type: While most standard batteries are flooded lead-acid, you can also consider an absorbed glass mat (AGM) battery for premium performance, especially if your car came with one from the factory.
Where is the battery on an Audi A4 2008?
That. And remove next carefully lift the spare wheel grab it from the center. Pull him up and out of the car. So you’ll see we have this plastic.
Which battery is best for Audi?
The best battery for an Audi is typically a high-quality AGM (Absorbent Glass Mat) battery, though the specific size and type should match your car’s original specifications. Leading brands to consider include X2Power, Interstate, Optima, Duracell, and Varta, but the most critical factors are getting the right group size (like 48 or 49) and ensuring it’s correctly coded to the vehicle’s computer after installation.
You can watch this video to learn how to replace and code an Audi or VW battery: 1mHayden SchreierYouTube · Sep 5, 2025
Battery type and brands
- AGM (Absorbent Glass Mat): Audi vehicles, especially those with start-stop systems, often require AGM batteries, which are a sealed, spill-proof, and more robust type of lead-acid battery. They are more resistant to vibration and extreme temperatures and generally last longer than traditional batteries.
- Recommended brands:
- X2Power: Specifically mentioned as a high-performance AGM option for Audi vehicles.
- Interstate: A popular and reliable choice with a strong track record in Audi and VW vehicles.
- Duracell: A quality brand available through stores like Batteries Plus, and some users have found them to be excellent replacements.
- Varta: An original equipment (OE) supplier, making their batteries a very reliable option.
- Optima: Known for durability and often recommended by Audi owners.
- Bosch: Offers high-performance batteries with a long lifespan.
Sizing and specifications
- Match the original battery: The most important step is to get the correct battery size for your specific car. Check your owner’s manual or the label on the old battery for the correct “group size,” which might be a number like 48 (H6), 49 (H8), or 51R.
- Look for matching specs: Ensure the replacement has a similar or greater Cold Cranking Amps (CCA) rating and Amp-hour (Ah) capacity.
Installation and programming
- DIY or professional: While you can replace the battery yourself, it’s crucial to properly program the new battery to the vehicle’s computer system.
- Why programming is essential: Audi vehicles use a Battery Management System (BMS) that needs to know the battery has been replaced to properly manage charging and power distribution. Without programming, the system won’t recognize the new battery, which can lead to reduced battery life and performance issues.
- How to program: Programming can be done with a specialized diagnostic tool, such as an OBD-II scanner, which are available from specialty auto parts stores or can be rented.
- Dealer option: If you are not comfortable with the process, your Audi dealer can perform the replacement and programming for you, though this may be more expensive.
What battery does a 2008 Audi A4 take?
Duralast Group Size 94R H7 Battery H7-DL.
