Crankshaft Audi A4 B8 Q3 8U Q5 8R 2.0 TDI Diesel Engine Unit 03L105021G

Crankshaft Audi A4 B8 Q3 8U Q5 8R 2.0 TDI Diesel Engine Unit is an original component from the Crankshafts group, designed for Audi diesel units. This used crankshaft provides a solid foundation for a professional repair of the lower part of a diesel engine, ensuring proper operation of the crank-piston system and stable load transfer in the 2.0 TDI engine.

Specifications and technical data

• SKU: 03L105021G
• Mark: Audi
• Condition: Used
• OEM Part Number: 03L105021G
• Substitutable numbers: 03L105021G, 03L 105 021 G
• Fuel type: Diesel
• Category: Crankshafts

Purpose and role in a diesel engine

The presented crankshaft is a structural component responsible for converting the reciprocating motion of the pistons into rotational motion, which is crucial for the operation of a diesel engine. In Audi 2.0 TDI units, it is responsible for:

• stable guidance of connecting rods and pistons across the full RPM range,
• transferring high loads characteristic of diesel engines,
• maintaining the correct geometry of the crank-piston system,
• cooperation with the flywheel, bearings, and lubrication system.

Thanks to the factory design by Audi, the crankshaft maintains appropriate rigidity and balance, which promotes smooth engine operation and reduces unwanted vibrations.

Benefits of using an original Audi crankshaft

Choosing an original crankshaft from the Audi group allows you to maintain engine performance parameters in accordance with the manufacturer's specifications. The most important advantages include:

• Factory fitment for 2.0 TDI engine blocks used in A4 B8, Q3 8U, and Q5 8R models.
• Compatibility with stock bearings, connecting rods, and lower engine components.
• Possibility to use existing Audi service documentation during installation and inspection.
• Consistency with other crankshaft system elements, which facilitates diagnostics and future service.

A used, original crankshaft is often a rational solution for diesel engine overhauls, allowing for a technically sound repair while maintaining a favorable cost-to-quality ratio.

Condition, verification, and service application

The item is offered as a used part, which in practice means it comes from disassembly and can be used as a base for further machining or installation after a standard workshop inspection. Before installation, it is recommended to:

• check the surface of the main and connecting rod journals,
• verify any radial runout on a balancing machine,
• inspect oil channels for patency,
• adjust bearings to actual dimensions after metrological measurements.

A crankshaft prepared in this way can be used both for a partial overhaul of the lower engine section and for a full rebuild of the 2.0 TDI unit, while adhering to Audi service procedures.

Audi crankshafts – expansion and engine system modernization

If you are planning a comprehensive repair or modernization of the engine area in your Audi and need other elements from the same group, such as additional shafts, fasteners, or compatible crank system components, check the available parts in the Audi crankshafts category.

Additional technical materials

For users interested in a broader context of engine unit modifications and the impact of mechanical changes on engine performance characteristics, an article dedicated to exhaust systems and performance components may be helpful. More information can be found in the material: Performance exhaust system: used manifolds and sports catalytic converters on the road.