Overfilling power steering fluid can cause leakage, which can reach the reservoir and cause foaming. Foaming can lead to premature component wear and less lubrication in the reservoir, resulting in early component failure. When the power steering fluid heats up and expands, it can be expelled from the reservoir through the vent, causing leakage and a messy engine compartment. Leaking fluid could get onto the belts, causing them to slip or break, and fluid could get on the exhaust, causing a possible fire hazard. Too much fluid can also make the pump build up too much pressure, which can cause the weakest spot to pop, such as a hose. Therefore, it is important to maintain the proper levels of power steering fluid and avoid overfilling it. If you do overfill the power steering fluid, you can remove the excess fluid with a turkey baster or syringe.