Audi 2.5 TDI V6 (2003)

The Audi 2.5 TDI V6 diesel engine (circa 2003) is a 2.5-litre six-cylinder turbocharged diesel power unit widely fitted in the Audi A4 (B6) and Audi A6 (C5) sedans and estates of the early 2000s. Known for its smooth torque delivery and solid real-world fuel economy, this V6 TDI combines a robust construction with turbocharging and intercooling to generate around 163 hp (120 kW) and about 310 Nm of torque — providing confident mid-range pulling power from low engine speeds.

In the Audi A4 B6, the 2.5 TDI delivers a blend of diesel efficiency and relaxed performance, enabling brisk acceleration and relaxed highway cruising with good fuel consumption figures. In the Audi A6 C5, the same engine offers strong mid-range torque suitable for heavier sedan or estate bodies, giving dependable performance and decent economy for its class.

Thanks to its V6 layout, the 2.5 TDI provides smoother operation and better torque spread than smaller 4-cylinder diesels of the era, making it a popular choice for drivers seeking a balance of comfort, torque, and diesel efficiency. It’s commonly found with both front-wheel drive or quattro all-wheel-drive configurations, depending on the vehicle.