Audi A8 S8 D3 Gearbox Oil Cooler Heat Exchanger 4E0317021A

Audi A8 S8 D3 Gearbox Oil Cooler Heat Exchanger is an original component from the Oil coolers and lines group, designed specifically for the drivetrain system in premium Audi models. This used OEM part ensures factory-fit, stable transmission operating parameters, and predictable cooling system performance even under heavy loads.

Specifications and technical data

• SKU: 4E0317021A
• Mark: Audi
• Condition: Used
• OEM Part Number: 4E0317021A
• Substitutable numbers: 4E0317021A, 4E0 317 021 A, B53990008, 09E409061, 09E 409 061
• Part type: Oil Cooler
• Category: Engine Oil Coolers & Lines

Function and application of the heat exchanger

The presented heat exchanger is responsible for controlling the oil temperature in the automatic transmission, which has a direct impact on the durability of the gearbox, the smoothness of gear shifts, and the safety of the entire drivetrain. By exchanging thermal energy with the engine cooling system, it stabilizes oil operating conditions, reducing the risk of overheating during city driving, towing, or dynamic acceleration.

A properly functioning gearbox oil cooler in the Audi A8 / S8 D3 helps maintain:

• consistent oil pressure in the automatic transmission,
• repeatable shift points,
• reduced wear on friction elements and seals.

Benefits of using an original Audi oil cooler

Choosing an original heat exchanger from the Oil coolers and lines group means maintaining the factory characteristics of the transmission. The OEM design is engineered for specific oil and coolant flow parameters, meaning the system does not require additional modifications or adaptations. This is a particularly beneficial solution for servicing high-end vehicles, where predictability and compliance with manufacturer documentation are paramount.

The most important advantages of using this oil cooler in the Audi A8 / S8 D3 include:

• factory fitment for the cooling and transmission system,
• preservation of the original oil flow geometry,
• reduced risk of leaks resulting from ill-fitting aftermarket replacements,
• easier future diagnostics thanks to compliance with Audi service documentation.

Installation and operational characteristics

The gearbox oil cooler in the Audi A8 / S8 D3 is a component that operates under demanding thermal conditions, which is why it is worth checking the condition of oil lines, clamps, and seals during replacement. Using an original heat exchanger facilitates installation – mounting points and connection ports are consistent with the factory setup, which shortens workshop time and reduces the risk of leaks after starting the system.

When servicing the oil cooling system, it is also recommended to:

• check the cleanliness of the transmission oil,
• verify the patency of the oil lines,
• verify the correct operation of the main engine cooling system.

Part condition and vehicle compatibility

The offered heat exchanger is a used OEM Audi component, which allows you to combine a favorable price with the preservation of the original technical specification. Before installation, it is recommended to perform a standard verification of tightness and the cleanliness of oil and cooling channels, in accordance with service procedures used for premium class vehicles.

To correctly select a gearbox oil cooler for a specific version of the Audi A8 or S8 D3, it is worth using the OEM part number and available interchangeable numbers visible in the technical specification section – this helps avoid mistakes with different engine and transmission variants.

Cooling system service expansion and additional materials

If you are planning a comprehensive repair or upgrade of the oil cooling system area in your Audi and need other components from the same group, such as additional coolers, oil lines, or connectors, check out the available parts in the Audi oil coolers and lines category.

When working on the cooling system in high-end cars, it is worth considering the impact of high external temperatures on the stability of the entire system. Practical tips regarding operation and service can be found in the guide Summer heat vs. cooling system: used coolers and fans as a guarantee of savings, which discusses how properly selected used components can support safe and economical vehicle operation.

If you care about completing repairs efficiently and reducing vehicle downtime in the workshop, the article Availability of car parts off-the-shelf vs. repair time – how used OEM parts shorten workshop stays? may also be helpful, describing the practical benefits of choosing readily available original used parts.