A power steering pulley is a pulley used to drive a power steering pump on an automobile or truck. Whether it is powered by a single V-type belt or a serpentine belt, the power steering pulley is typically sized to permit faster-than-engine-speed operation of the power steering pump. The typical power steering pulley requires a special tool to remove and replace the pulley from the pump. With an adjustment mechanism not available on many power steering pumps, the remedy for a squeaking steering pump belt is quite often a small spray application of belt dressing.
Most power steering pulley designs use a solid steel stamping for the construction of the pulley. This is due to the speed and torque with which the pump is turned. A lightweight power steering pulley could conceivably bend or break under such severe loads. Removal of the pulley is typically only required to change the power steering pump or to replace a leaking pump seal. With the seal on the pulley shaft, it would be impossible to service the pump seals without removing the power steering pulley. Many auto parts supply stores offer loaning or rental of the special tool required to remove the pump's pulley, so it is not usually necessary to purchase the tool for a single use.
If it becomes necessary to replace a power steering pump in any vehicle, it is almost a certainty that the power steering pulley will need to be removed from the old pump and reinstalled on the new pump. Most new power steering pumps are sold without a pulley. This makes the part easier to box and somewhat less expensive to sell. Many parts supply stores will remove the pulley for a customer at the time of purchasing the new pump. This works to both the store's as well as the customer's benefit in that the store does not need to loan the tool out in order to sell a power steering pump and the customer does not need to worry about removing the pulley.
Most sales of power steering pumps require a core pump to be returned to the store in order to be rebuilt and resold by the manufacturer. This makes the removal of the pulley from the old pump mandatory. By having the store salesman remove the power steering pulley, the new pump can be more accurately compared to the original and the pulley can be installed in the store, ensuring the pulley fits the shaft of the new pump perfectly.