What Is the Average PSI of a Car's Power Steering Pump?by Richard Rowe
Power steering does more than make life a little easier -- it makes cars a lot quicker. Before power steering, manufacturers could build a box with a quick gear ratio for rapid reflexes, or a much slower gear ratio for easier turns. But since tighter boxes made steering harder, they often had to install giant, school-bus steering wheels for extra leverage on them. The modern hydraulic steering system packs a load of power in a small package, and develops incredible pressures to do it.
All cars are different, and require different pressures. Heavy vehicles and cars with very quick-ratio steering boxes typically require higher pressures than lighter and lower-performing vehicles. At idle with the steering wheel static, a typical power steering pump holds about 80 to 125 psi in the output line. Yank the steering wheel a couple of times in rapid succession -- causing the pressure-release valve to flutter open and shut -- and a typical modern pump might momentarily put between 1,000 and 1,500 psi through the lines. Older and lower-performing pumps might run 850 psi of momentary pressure or less, while heavy-duty off-road pumps may sustain 1,600 or more. High-performance pumps can jump to 2,500 psi before the valve releases. and hold upward of 8,000 to 10,000 psi internally before bursting.
Richard Rowe has been writing professionally since 2007, specializing in automotive topics. He has worked as a tractor-trailer driver and mechanic, a rigger at a fire engine factory and as a race-car driver and builder. Rowe studied engineering, philosophy and American literature at Central Florida Community College.