Steering Services
Subaru Power Steering Systems
It goes without saying that steering, along with brakes, is the most critical system in your Subaru, affecting both safety and driveability. Makers of quality cars mostly use the rack-and-pinion system, which provides the most direct and accurate steering and the most "road feel". This is naturally the system used by Subaru on all their models. As with all Subaru systems, Subaru steering is designed and manufactured to provide maximum safety and control. Subaru steering is direct and accurate, and provides excellent road "feel" to the driver.
Warning: Avoid Second Hand!
Second hand components of any kind are always to some degree an unknown quantity. Flaws often are not evident until the parts are in service. With vital safety systems like steering and brakes, you don't want to discover defects in operation. Steering components might have stress fractures in the metals that are not detectable, and the level of wear is difficult to judge accurately. Never compromise with safety.Two types of power steering assistance
Type 1—Subaru hydraulic steering
As with most modern motor cars until recently Subaru employed a hydraulic steering system, whereby input from the steering wheel was transmitted via the power steering pump, through hydraulic hoses, to the rack, thence by direct tie rod connection to the front wheels. More recently, Subaru, in line with modern developments, has been moving to an electrical system.
Type 2 Subaru electric steering
This system incorporates a variable output electric motor directly coupled to the steering rack. This motor is controlled by a computer, which acts on a signal from a torque sensor in the steering column to increase or decrease current to the electric motor providing varying degrees of assistance. This system is fitted to most current Subaru models and will eventually be used across the whole range. While some drivers complain that road feel is diminished, the electric system is inherently more reliable and efficient.VDC
Both power assist systems are integrated into Subaru's Vehicle Dynamics Control system, (VDC) on selected models. The VDC is a computer based system that automatically adjusts suspension brakes, and steering to suit road conditions and driving style.Subaru Steering System Components
Subaru's steering systems comprise several components. These components are all interrelated in that failure of one component will lead to cascading failure of other components.Power steering pump
Driven by a belt from the engine, the power steering pump pushes hydraulic fluid into a cylinder within the steering rack to assist steering. There are two types of power steering pump:
Type 1: 1991 – 2001
The type 1 pump uses an integrated power steering fluid reservoir and does not use a suction hose. These pumps have been very reliable with few reported problems, or internal construction issues other than fluid leaks after 5-7 years of service. These pumps are easily serviceable and parts are readily available. The common reported problems with this model are leaking top lids. These lids have a large rubber O-ring which is difficult to replace. Once leakage sets in, many owners choose to replace the pump. These pumps were larger and bulkier than the type 2 pumps and were incompatible with new slimline body designs.
Type 2: 2001 - Current
The type 2 pump has a separate remote fluid reservoir and utilises a suction hose at the low pressure end of the system to return fluid to the pump. These pumps are designed by Subaru as non-serviceable items but because of their high replacement cost, after market suppliers have entered the market with new replacement parts. Because the fluid reservoir is remote from the pump, Subaru incorporated a filter at the base of the reservoir. This filter is difficult to access and is often neglected during services. The most common cause of pump failure is blockage of this filter leading to eventual catastrophic pump failure. Damage is cumulative over time and there is little warning of impending failure.Steering Rack and Pinion
The steering rack is mounted across the engine bay bulkhead and is connected to the front road wheels via tie rods with flexible links. Racks on Subaru models from 1991- 2006 used a four-bolt mounting system with the rack fastened by two bolts at each end of the rack. Later models used a two-bolt system with one end hooked into the bulkhead and the driver's side bolted down. Both systems have proven to be highly durable and reliable, and have provided a positive driving experience for Subaru owners.Suction hose (Low pressure power steering return hose)
This is the largest hose in the power steering system. It is fitted at the low pressure end of the system and returns fluid to the power steering pump. With age, this hose becomes brittle and porous, causing air to leak into the system. This may produce symptoms that indicate a failing pump. Many unwary owners have been caught out replacing pumps when only the suction hose was required.Hydraulic hoses ADS replacements
These are the two high pressure hoses that run from the pump to the rack and back to the pump again. With age these become brittle and start to leak around the crimped joints and O-rings. OEM replacements are expensive and usually not in stock and we do not advise fitting second hand replacements. ADS has engineered a solution. We have sourced high quality generic hydraulic hoses, and we crimp these ourselves to suit Subaru power steering applications for a fraction of the price of new OEM replacement hoses.Diagnosis and repair—tell-tale signs of steering issues
Signs of impending steering failure include:- Excessive free play in the steering
- "tram-tracking" over uneven surfaces
- Steering pulling to one side or the other
- Inconsistent steering effort from hard to easy
- Unusually heaving steering
- Knocking noises when turning the wheel from one direction then another
- Groaning or squealing noises from under the bonnet while turning the wheel
- Steering rack fluid leaks or smells of hot fluid
