On most vehicles, the high-pressure hose is the braided line from the power steering pump to the steering gear; the other hoses are the low-pressure supply and return lines (reservoir to pump and gear back to reservoir).
Understanding the hoses in a power steering system
The power steering system relies on three hoses to move fluid through the circuit. Each serves a different job, and identifying them helps with inspection, maintenance, or quick repairs.
- High-pressure hose — This is the braided metal outer line that runs from the power steering pump to the steering gear (rack or box). It carries fluid at high pressure (typically several hundred to over 1,000 psi). The exterior braid and rigid fittings make it visually distinct from the others.
- Suction/low-pressure hose (reservoir to pump) — A rubber hose that feeds fluid from the reservoir into the pump. It operates at ambient or near-ambient pressure and is more flexible than the high-pressure line.
- Return/low-pressure hose (steering gear to reservoir) — This hose carries fluid returning from the steering gear back to the reservoir. It is also a rubber hose and is usually larger in diameter than the suction line, though still flexible.
In most designs, the three hoses form a loop: fluid is drawn from the reservoir into the pump via the suction line, the pump pressurizes it through the high-pressure line to the steering gear, and the gear returns fluid to the reservoir through the return line. This arrangement helps keep the system properly lubricated and pressurized for smooth steering assist.
How to identify the hoses on your vehicle
Use these practical clues to distinguish them on your car. Start with a visual check and then trace the routing to confirm connections. If you’re unsure, consult the vehicle’s service manual or a factory diagram for your exact model.
- Locate the power steering pump and the steering gear (rack or box). Identify the line leaving the pump toward the gear.
- Note the hose that is braided metal on the outside and has metal fittings at both ends; this is the high-pressure line.
- Look for hoses connected to the reservoir. The hose going from the reservoir to the pump inlet is the suction/low-pressure line, while the hose returning from the steering gear back to the reservoir is the return/low-pressure line.
- Trace the path: the high-pressure line typically runs directly from the pump outlet to the steering gear, with the other two lines routed more loosely between the reservoir, pump inlet, and gear.
Be aware that some vehicles use slightly different routing or have integrated lines, but the braided high-pressure hose versus rubber low-pressure hoses rule of thumb generally holds. Never disconnect or work on hydraulic lines while the system is pressurized or the engine is running; fluids can spray under high pressure and cause injury.
Summary
The key to telling the hoses apart is to look for the braided high-pressure line, which runs from the power steering pump to the steering gear. The other two hoses are low-pressure lines: the suction line from the reservoir to the pump and the return line from the steering gear back to the reservoir. Use the hose texture, routing, and fittings as your guide, and consult the vehicle’s service documentation if in doubt.