Ford F-150 2010 Owner's Manual page 310

Driving
WARNING: Vehicles with a higher center of gravity such as
utility and four-wheel drive vehicles handle differently than
vehicles with a lower center of gravity. Utility and four-wheel drive
vehicles are not designed for cornering at speeds as high as passenger
cars any more than low-slung sports cars are designed to perform
satisfactorily under off-road conditions. Avoid sharp turns, excessive
speed and abrupt maneuvers in these vehicles. Failure to drive
cautiously could result in an increased risk of loss of vehicle control,
vehicle rollover, personal injury and death.
• If the vehicle goes from one type of surface to another (i.e., from
concrete to gravel) there will be a change in the way the vehicle
responds to a maneuver (steering, acceleration or braking). Again,
avoid these abrupt inputs.
Parking
On some 4WD vehicles, when the transfer case is in the N (Neutral)
position, the engine and transmission are disconnected from the rest of
the driveline. Therefore, the vehicle is free to roll even if the automatic
transmission is in P (Park) or the manual transmission is in gear. Do not
leave the vehicle unattended with the transfer case in the N (Neutral)
position. Always set the parking brake fully and turn off the ignition
when leaving the vehicle.
WARNING: Always set the parking brake fully and make sure
the gearshift is latched in P (Park). Turn the ignition to the off
position and remove the key whenever you leave your vehicle.
WARNING: If the parking brake is fully released, but the brake
warning lamp remains illuminated, the brakes may not be
working properly. See your authorized dealer.
4WD systems
4WD (when you select a 4WD mode) uses all four wheels to power the
vehicle. This increases traction, enabling you to drive over terrain and
road conditions that a conventional two-wheel drive vehicle cannot.
Power is supplied to all four wheels through a transfer case. On 4WD
vehicles, the transfer case allows you to select 4WD when necessary.
Information on transfer case operation and shifting procedures can be
found in this chapter. Information on transfer case maintenance can be
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