Engine Oil and Fluid Recommendation for Audi A6, S6, SR6 (4A, C4; 4B2, C5) – A6 2.5 TDI, -quattro The main rule on which the correct selection of engine oil for a car is based is that you should not fill it with oil that seems in your opinion better than what the manufacturer requires. After all, not in all cases, compliance with later requirements in terms of the quality of engine oil indicates that it is suitable for your car.
  • Engine oil capacity, liter: 5.3-5.5
  • Manual transmission capacity, liter: 2.4-2.7
  • Automatic transmission capacity, liter: 9.0
  • Differential capacity, liter: 0.8/1.3/1.5
  • Power steering capacity, liter: 0.9
  • Cooling system capacity, liter: 10.0
  • Year: 1997-05

Engine oil

  • Synthetic oil: Longlife III 5W-30 (Longlife 3 5W-30)

Manual transmission

  • Synthetic gear oil: 75W90 GL5

Differential

  • Synthetic gear oil: 75W90 GL5

Power steering

  • Hydraulic fluid: CHF/Central Hydraulic Fluid

Cooling system

  • Antifreeze for the engine: Antifreeze G12 red