1996 Ford F150 Owner's Manual - Page 199

- The initial shift from two-wheel drive to 4x4 while the vehicle is moving can cause some momentary clunk and ratcheting sounds. This is the front drivetrain coming up to speed and the automatic locking hubs engaging and is not a cause for concern. - Because of possible damage to powertrain components, never shift from Two-Wheel Drive to 4x4 with the rear wheels slipping. To shift from 4x4 to Two-Wheel Drive: Push the 4x4 button; the 4x4 lamp on the instrument cluster will go out indicating the vehicle is in Two-Wheel Drive. This can be done at any speed. To disengage the automatic locking hubs, operate the vehicle in Two-Wheel Drive in the opposite direction for approximately 10 feet (3 meters) in a straight line. For example: If you were driving the vehicle forward in 4x4, the automatic locking hubs will disengage the next time the vehicle is driven in reverse in Two-Wheel Drive for approximately 10 feet (3 meters) in a straight line. If you were driving the vehicle in reverse in 4x4, the automatic locking hubs will disengage the next time the vehicle is driven forward in Two-Wheel Drive for approximately 10 feet (3 meters) in a straight line. Operating in two-wheel drive mode with the hubs locked increases fuel consumption, noise, vibration, and wear. For prolonged two-wheel drive operation on dry pavement, disengagement of the automatic locking hubs, which is not required for two-wheel drive operation, stops all 197