1997 Ford Aerostar Owner's Manual - Page 168

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. Automatic Transmission Operation (4R44E/5R55E) If your vehicle is equipped with an automatic transmission, it will be either a four speed overdrive transmission (4R44E) or a five speed overdrive transmission (5R55E). All 3.0L engines use the 4R44E transmission, while all 4.0L engines use the 5R55E transmission. Both transmission types have a lockup torque converter. Transmission operation is controlled by the Powertrain Control Module (PCM). 168