Audi A6 1994 2.5 diesel service and maintenance

Engine oil

Engine oil capacity: 5.2 litres (5.5 quarts)
Recommended oil type (Oil Viscosity Classification SAE) is 5W-40

Timing belt

Manufacturers recommended timing belt replacement interval for Audi A6 2.5 diesel is 100,000 km.
The experience of Audi A6 owners confirms that timing belt does in fact last for the specified mileage.
Running your car in aggressive environments (e.g. salt, sand, etc.) causes timing belt to degrade faster and reduces its lifespan; under such conditions, the belt may need to be replaced sooner.