In most Audi models with hydraulic power steering, the recommended fluid is Pentosin CHF 11S. Some models or later generations may use CHF 202, and newer Audis run electric power steering that requires no hydraulic fluid at all.
Understanding Audi's power steering systems
Power steering in modern Audis has shifted from hydraulic to electric in many models. Hydraulic power steering (HPS) uses a fluid reservoir and a pump to provide pressure to the steering rack. Electric power steering (EPS) uses an electric motor and control unit; in EPS, there is no dedicated steering fluid to check.
Hydraulic power steering (HPS)
In vehicles that still use a hydraulic system, the steering fluid acts as the hydraulic medium that translates the driver’s input into steering assist. The fluid must meet the manufacturer’s specification and tolerate the system’s temperature and viscosity ranges.
Electric power steering (EPS)
EPS systems rely on an electric motor and sensors. They do not use a conventional steering fluid reservoir, and some systems may provide minimal hydraulic assist only in specific configurations. In general, EPS reduces or eliminates the need for PS fluid.
Common fluids used by Audi
Here are the two fluids most commonly specified by Audi for hydraulic power steering across various models. Always confirm the exact spec for your model year and engine code.
- Pentosin CHF 11S
- Pentosin CHF 202
Note: These fluids are not universally interchangeable. If your car has EPS, there is no PS fluid to use. For models with hydraulic PS, always use the exact fluid specified by Audi for that year and model, and do not mix different fluids.
How to check and replace power steering fluid
The following steps outline how to verify the correct fluid and perform a top-up or replacement if needed. This guidance applies to vehicles with hydraulic PS; EPS vehicles should not be topped up with PS fluid.
- Consult the owner's manual or Audi official service information to confirm the correct fluid type for your vehicle.
- Locate and inspect the power steering fluid reservoir in the engine bay; check the cap for the required specification and the fluid level markings.
- Use only the approved fluid (e.g., CHF 11S or CHF 202) and avoid mixing fluids from different specifications.
- With the engine off, add fluid slowly up to the indicated level if the level is low; do not overfill.
- If you suspect a leak or the steering feels unusually noisy or stiff, have the system inspected by an Audi dealer or a qualified technician.
Concluding note: Fluid replacement and system service should typically be performed by a professional or at specified service intervals; mishandling can damage the pump, rack, or seals.
Summary
Most Audi models with traditional hydraulic power steering use Pentosin CHF 11S, with CHF 202 used in some versions. Electric power steering models do not require hydraulic fluid. Always verify the exact specification in your owner's manual or with an Audi service center before topping up or replacing fluid, and avoid mixing different fluids to preserve steering performance and longevity.