You are Running Low on Power Steering Fluid
A low level of power steering fluid is the number one cause of a steering wheel being hard to turn. The main purpose of the power steering fluid is to lubricate the power steering pump and to transmit pressure seamlessly throughout the system
A pump that runs dry can cause internal damage and put metal shavings in the power steering fluid system. If the belt is on and the fluid level is ok there is a good chance that the pump has failed and will need replacement. A coolant leak can lead to an overheating engine that can lead to a blown head gasket.
Having a steering wheel that is hard to turn is a pretty scary problem to have with your car. It is unsettling to go from easily steering to having such a vital function not perform the way that you are used to it performing.
It can be dangerous to drive when the steering wheel is hard to turn, as you may not be able to keep yourself safe on the road. You should pull over immediately, and schedule an inspection with a mechanic.
Power steering fluid is low: The force that allows your power steering to function properly is the result of the power steering fluid applying pressure against the piston inside the rack and pinion. As the amount of fluid in the power steering system diminishes, the amount of force that can be applied to the piston lowers.
The steering rack, which is part of the rack and pinion, is the primary part of your steering assembly, and works in conjunction with the power steering system. Steering racks can grow damaged over time as they develop wear and tear, and when they do, they make it much harder to steer your vehicle.
Symptoms of a power steering hard to turn