Power Steering Fluid

Most cars today are equipped with a power steering system. Many power steering systems use hydraulic power. These systems use a power steering pump driven by a belt from the crankshaft as shown below. The pump moves fluid under pressure through hoses to the steering gear. The pressure is used in the steering gear to reduce steering effort. A reservoir for fluid is attached to the rear of the pump. Checking the fluid level in this reservoir is a common under-hood maintenance job.

The fluid in the power steering system provides lubrication as well as the power assist. Low fluid level can cause a lack of power assist, excessive noise, and rapid part wear. The power steering fluid level should be checked at regular intervals.

CAUTION: Check the fluid level with the engine off to prevent possible injury from moving parts.

The fluid is checked at the pump reservoir with a dipstick attached to the reservoir cap. Before removing the reservoir cap, wipe the outside of the cap and reservoir to prevent dirt from falling into the reservoir. Pull the dipstick out and note the fluid reading. The fluid should be between the "hot" and "cold" mark on the dipstick. There are hot and cold marks because the fluid expands as it gets hot. If the level is below the "add" mark, you will have to add fluid to bring it up to the correct level. You should use only the type of fluid listed in the owner's or shop service manual. Older cars use automatic transmission fluid. Special power steering fluids are used on late-model cars. Add the correct amount of fluid and replace the dipstick.