1996 Ford Aerostar Owner's Manual - Page 172

Steering Your Vehicle Your vehicle comes with power steering. Power steering uses energy from the engine to help steer your vehicle. If the amount of effort needed to steer your vehicle changes at a constant vehicle speed, have the power steering system checked. If the power steering system breaks down (or if the engine is turned off), you can steer the vehicle manually but it takes more effort. Never hold the steering wheel to the extreme right or left for more than five seconds if the engine is running. This can damage the power steering pump. NOTE: After any severe impact such as striking large potholes, sliding into curbs on icy roads, or a collision involving the front end, observe the steering wheel alignment. If the spokes of the steering wheel seem to be in a different position while going straight down the road, have the front suspension and steering checked for possible damage. Electronic 4-Wheel Drive (E-4WD) (If equipped) If your vehicle is equipped with the E-4WD option, power is provided to all four wheels whenever you press the accelerator pedal. It improves both handling and traction during difficult driving conditions, adjusting automatically to your driving needs. Because the entire E-4WD system is controlled by a microprocessor, your vehicle is not equipped with the switch or shift lever used with most traditional 4WD vehicles. The microprocessor does all the adjusting for you. 191