This blog post discusses the VW hydraulic power steering fluid system. Wondering what type VW hydraulic power steering fluid your VW uses and how often it should be changed? We answer that and also discuss the many advancements in VW hydraulic power steering systems. As well as provide a brief overview of how to change your VW hydraulic power steering fluid.
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- Why Is Flushing and Changing Your VW Hydraulic Power Steering Fluid So Important?
- Overview of How to Change VW Hydraulic Fluid
Why Is Flushing and Changing Your VW Hydraulic Power Steering Fluid So Important?
In this article we will discuss a little more about the history of the VW hydraulic power steering fluid system. Why is flushing and changing your Volkswagens hydraulic power steering fluid so important? Also, we will discuss the advancement in different VW hydraulic power steering systems and also which power steering fluid should be used in your vehicles application and give you a brief overview on how to change your VW hydraulic power steering fluid.
As an independent VW service garage and parts specialist with over 27 years of hands-on experience, we've seen many mechanical breakdowns on vehicles. Experience has shown that changing your fluids is the single most important preventive maintenance routine you can perform to avoid vehicle breakdowns. Yet, for many VW owners, this seems to be one of the most neglected areas of maintenance. Thoroughly flushing your fluids at the proper intervals can help your car reach 200,000 miles and beyond! Changing your VW hydraulic power steering fluid prevents failure of expensive steering pumps, rack and pinions, and other steering related parts.
Some suggest that you don't need to change your VW hydraulic power steering fluid. Most vehicle manufacturers scheduled maintenance list don’t even mention changing your hydraulic power steering fluid. We feel this isn't logical. VW power steering pump is just one component of concern. The moving internal components of the steering pump and steering rack and pinion mesh and wear with one another, creating metallic particles that contaminate VW hydraulic power steering fluid. It's important to change the VW power steering fluid as a part of your preventive maintenance schedule. We recommend changing your VW hydraulic power steering fluid as a first step when attempting to solve hydraulic related issues, such as a noisy steering pump or the intermittent loss of power assisted steering. Vehicles operating in hotter climates or that are subjected to driving in heavy city traffic should have their hydraulic power steering fluid changed every 50,000-60,000 miles. It's good preventive maintenance and is inexpensive when compared to the replacement of an VW steering pump or VW steering rack and pinion.
A Brief History of The VW Hydraulic Power Steering Fluid Systems
In 1980 Volkswagen was considered an innovative automobile. The early VW models were equipped with a unique hydraulic pump that simultaneously performed both the power assisted braking and power assisted steering. This dual functioning system was used on many Audi VW models up until around 1997-1998.
Back then, a double vain hydraulic power steering pump performed these two functions (power assist braking and power assist steering), requiring an advanced hydraulic oil that could properly function under the inherent high operating pressures and temperatures generated within this system. This unique system spawned a new era of hydraulic power steering fluids, a mineral based (OE Part Number A0E 041 020 10 or CHF 7.1) hydraulic steering fluid in the early 1980s, later a synthetic based fluid (VW Quality Specification TL 52 146.00, VW OE Part Number G 002 000 A2 or CHF11s) in the 1990s and now the fully synthetic fluid (OE Part Number G 004 000 M2 or CHF 202) in the mid to late 2000.
Today, VW models use a simpler design (compared to what was used back in the 1980s and 1990s). The single vain steering pumps of today typically only generate hydraulic pressure for the power assisted steering function and has a lower operating temperature. The mounting location of the steering pump differs depending on model and engine configuration and may vary on where its mounted. Some are mounted near other heat generating components (i.e. turbochargers). Today's hydraulic fluid must facilitate proper steering pump operation, withstand high temperatures, and ensure reliability over a longer period and under all vehicle operating conditions. Also, since the late 2000’s it’s hard to find a car that has a power steering pump.
Many VW models have transitioned to an electronic pump or an electronic rack and pinion. This allows for more precise steering, less hydraulic power steering components and the ability to calibrate the amount of steering needed depending on driving variables. Some power steering systems can completely turn off or minimize the power steering assistance when it’s not needed at higher highway speeds. This allows for a more economical driving vehicle with some improvement in fuel economy. Many of these systems still have a small amount of hydraulic power steering fluid but in most cases are not serviceable or can’t be flushed.
Can You Mix Older Mineral Based VW Hydraulic Power Steering Fluid with the Updated and Newer Synthetic Power Steering Fluid?
There has been a good measure of controversy over this question. Here is what our own experience has shown. Over the last decade we've had no compatibility problems mixing the CHF 7.1 non-synthetic mineral base fluid and the CHF 11S synthetic based VW hydraulic power steering fluid. No problems with our own vehicles and no problems with our customers vehicles. Our success in mixing the 2 Volkswagen hydraulic power steering fluids coincides with the VW tech bulletin 48-89-T07 issued in November 1989. It states, "The new [synthetic VW quality specification TL 52 146.00, OE part number G 002 000 A2 or CHF11s] and old power steering fluid [non-synthetic CHF 7.1 OE part number A0E 041 020 10] can be mixed if necessary." So according to VW, you can mix the 2 Volkswagen hydraulic power steering fluids. Even though the composition of the fluid changed from a synthetic base oil vs a non-synthetic mineral oil.
1980-1989 VW models came filled from the factory with OE part number A0E 041 020 10 or CHF 7.1 mineral based fluid.
1990-2005 VW models have come filled from the factory with the synthetic VW spec TL 52 146.00, OE part number G 002 000 A2 or CHF11s.
2006-current VW hydrailic power steering fluid systems are filled with the fully synthetic VW TL 52 146.01, G 004 000 A2, CHF202 spec.
Important Note: Never mix generic power steering fluid or other fluid with VW power steering fluid (G002000) or CHF202 (G004000). If you or someone else did, flush the VW power steering fluid as described below. When flushing your hydraulic steering fluid system, we recommend upgrading to the newest fully synthetic VW G004000 fluid specification.
Overview of How to Change VW Hydraulic Fluid
Demonstated/Applies to 1998-2005 VW Passat Models
We always recommend having an A.S.E. certified VW mechanic change your VW hydraulic power steering fluid. Refer to the factory service manual for VW hydraulic system instructions. Always wear gloves and wear safety goggles when handling VW fluids. Never start the vehicle without VW hydraulic power steering fluid in the fluid reservoir.
This is a basic overview of what is involved when flushing VW hydraulic power steering fluid. It is not intended to replace the factory service manual. Please refer to the factory service manual for detailed instructions.
- The VW hydraulic fluid reservoir is located on the driver’s side inner fender well in the engine compartment right behind the head lamp.
- Locate the hydraulic power steering cooler tubing in front of the radiator. Find the rubber hose that attaches to the tubing located near the driver’s side lower corner of the radiator. Disconnect the hose and drain the VW hydraulic fluid.
- Flush the old VW hydraulic fluid out of the VW steering rack and pinion. Turn the steering wheel full lock side to side about 10-20 times. This sequence pushes the VW hydraulic fluid out of the steering rack and into the fluid reservoir for it to drain out.
- Some models have a sleeve type filter screen inserted in the fill hole of the VW hydraulic fluid reservoir. If it has the filter, remove it and clean it. Clean out the sediment that also exists on the bottom of the VW hydraulic fluid reservoir.
- Reinstall the VW hydraulic fluid hose removed in step (2) and fill the reservoir with G002000/G004000 VW hydraulic fluid.
- Start the engine and let the car run for 10 seconds at idle. Important! Do not rev the engine up. Revving the engine could cause hydraulic pump damage. Repeat this step several times while confirming the hydraulic fluid reservoir is full.
- Refill the VW hydraulic fluid reservoir again with G002000 hydraulic steering fluid.
- Start the engine and let the car run at idle, turn the steering wheel full lock about 10 times from side to side.
- Turn the engine off and fill the hydraulic fluid in the reservoir to the maximum capacity level as indicated.