The 2008 Audi A4 equipped with the 3.2-liter V6 engine (engine code BKH) is a refined sedan that demands precise maintenance to preserve its performance and longevity. Operating a high-revving European powerplant requires lubricants that meet strict OEM standards for viscosity, shear stability, and additive chemistry. Using the correct fluids ensures optimal thermal protection, reduces engine wear, and maintains the smooth shifting characteristics expected from an Audi transmission system. This guide details the specific lubrication requirements and recommended AMSOIL products to keep this vehicle running at its peak.
Recommended AMSOIL Products
- AMSOIL 5W-40 MS 100% Synthetic European Motor Oil – Designed specifically for the unique demands of gasoline, diesel, and hybrid European vehicles, this oil provides a precise blend of synthetic base oils and premium additives that exceed Audi standards.
- AMSOIL 5W-40 FS 100% Synthetic European Motor Oil – Offers extended protection and superior thermal stability, making it an ideal choice for maintaining engine cleanliness and wear protection in this high-performance engine.
- AMSOIL 0W-40 FS 100% Synthetic European Motor Oil – Provides excellent cold-start protection while maintaining high-temperature viscosity, ensuring immediate lubrication upon startup in various climates.
- WIX Oil Filter – Features premium filtration media that offers improvements over original equipment manufacturer-branded filters, capturing contaminants to protect the engine.
- MANN-FILTERS Air Filters – Includes high-quality filtration media designed to maximize airflow and trap dust, ensuring the engine breathes efficiently.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A pre-mixed 50/50 formulation that protects cooling system metals, gaskets, and hoses while being phosphate-free and silicate-free.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated formula that greatly surpasses standards for metallic corrosion and erosion, offering long-term protection up to 150,000 miles.
- AMSOIL 100% Synthetic CVT Fluid – Provides exceptional metal-to-metal frictional properties for automatic transmissions requiring the 01J fluid specification.
- AMSOIL 75W-90 Manual Transmission & Transaxle Gear Lube – Protects against increased heat and pressure with outstanding cold-flow properties and excellent seal compatibility for manual gearboxes.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent ABS and traction-control responsiveness with a stable viscosity over a wide temperature range.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – Helps seals remain soft to prevent leaks while providing strong anti-wear protection and resistance to heat.
Engine Oil and Filtration Specifications
The heart of the 2008 Audi A4 3.2L is the BKH engine, a naturally aspirated V6 that produces smooth power and requires synthetic lubricants to function within its tight tolerances. The factory service manual specifies that the oil must meet the applicable Audi and Volkswagen oil quality standards. For this engine, the recommended viscosity grades include 5W-40, 5W-30, 0W-40, and 0W-30, with 5W-40 being a primary recommendation for European vehicles to ensure optimal protection across the engine’s operating temperature range.
The total oil capacity for a drain and filter change is 6.9 quarts. It is crucial to torque the oil drain plug to 22 ft/lbs during reassembly and to check the oil level after refilling to ensure the correct volume is present. When the appropriate synthetic oil that meets the specific Audi standards is not available locally, it is important to select a viscosity grade suitable for the local climate and operating conditions. AMSOIL 5W-40 MS and 5W-40 FS are formulated to meet these rigorous European specifications, offering protection that exceeds the highest industry standards.
Filtration is equally critical for this engine. The WIX Oil Filter (Part Number 57204-EA) is the recommended choice, offering premium media that outperforms OEM-branded filters in capturing particulate matter. Additionally, maintaining proper airflow is essential for engine efficiency and power delivery. The MANN-FILTERS Air Filter (Part Number C271921-EA) ensures that the engine receives clean air, improving performance and protecting internal components from abrasive wear.
Transmission and Differential Care
Proper lubrication of the transmission system is vital for the smooth operation of the 2008 A4. The vehicle utilizes different fluid types depending on whether it has an automatic or manual gearbox. For the automatic transmission (specifically the 01J unit), the required fluid is the 01J/VTF02 specification. The total fill capacity for this unit is approximately 7.9 quarts. AMSOIL 100% Synthetic CVT Fluid is the ideal choice for this application, providing exceptional metal-to-metal frictional properties that ensure smooth shifts and reduce wear in the torque converter and transmission clutches.
For models equipped with a manual transmission (01X/SL148 specification), the capacity is 6.3 pints. AMSOIL 75W-90 Manual Transmission & Transaxle Gear Lube is recommended for manual applications. This gear lube is friction-modified to protect brass synchronizers and includes excellent seal compatibility to prevent leaks. It resists the high heat and pressure found in manual gearboxes and offers outstanding cold-flow properties for reliable shifting in low temperatures. When performing service on a manual transmission, ensure the fill and drain plugs are torqued to 33 ft/lbs.
Cooling System and Brake Fluid
The cooling system for the 2008 Audi A4 3.2L has a total capacity of 9.5 quarts. Maintaining the correct coolant mixture is essential to prevent corrosion, overheating, and freezing. AMSOIL offers two primary options for this requirement. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a ready-to-use, 50/50 pre-mix formulation containing an organic acid technology (OAT) that protects all cooling system metals, gaskets, and hoses. It is free from phosphates, nitrates, nitrites, silicates, borates, and amines, ensuring compatibility with the vehicle’s aluminum components.
For those who prefer a concentrated option, AMSOIL Propylene Glycol Antifreeze and Engine Coolant offers a robust solution. This concentrate requires mixing with distilled or high-quality water and provides protection up to 150,000 miles or five years. It is designed to prevent metallic corrosion and erosion while being compatible with all other antifreeze colors and formulations.
Regarding braking safety, the vehicle specifies a DOT 4 hydraulic brake fluid (P/N B 000 750 M3). AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid is the recommended fluid for this application. Its synthetic formulation ensures excellent responsiveness from the ABS and traction-control systems while maintaining a stable viscosity across extreme temperature fluctuations, ensuring consistent pedal feel and stopping power.
Additional Fluid Maintenance
Power steering systems in this generation of Audi A4 benefit from high-quality synthetic lubricants to prevent wear and ensure quiet operation. The recommended fluid is the AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid. This fluid reduces friction and helps seals remain soft, which prevents leaks and extends the life of the power steering pump. It offers excellent high-temperature protection and low-temperature performance, formulated specifically for quiet operation in modern hydraulic steering systems.
About the Vehicle
The 2008 Audi A4 represents a mature generation of Audi’s compact luxury sedan, built on the B7 platform which was later succeeded by the B8 generation. This era of the A4 is particularly well-regarded for its mechanical simplicity and reliability, especially in the 3.2-liter V6 configuration. Unlike the more common 1.8T or 2.0T models of the same vintage, the 3.2L BKH engine is a naturally aspirated unit that offers a smooth, linear power delivery that many enthusiasts prefer for daily driving.
Originating from Germany, the Audi A4 line has always been positioned as a benchmark for compact luxury vehicles, competing directly with the BMW 3-Series and Mercedes-Benz C-Class. The B4 platform (2002-2008) established the A4’s reputation for solid build quality and refined handling dynamics. The 3.2L variant, producing roughly 255 horsepower, provides ample power without the complexity of turbocharging, which can be a factor for long-term ownership costs.
Owners of the 2008 A4 often appreciate its balanced driving character, combining sporty handling with a comfortable ride quality suitable for daily commutes or weekend drives. The interior design of this period features the hallmark Audi focus on functionality and ergonomics. While the vehicle is now several years old, its robust engineering means that with proper fluid maintenance, such as the AMSOIL recommendations detailed above, it continues to offer a premium driving experience that rivals much newer vehicles. The 3.2L model, in particular, is often sought after by drivers who value the acoustic signature of a naturally aspirated V6 engine combined with the timeless design of the B7 chassis.