Ford Explorer 2009 Owner's Manual page 153

Ford Motor Company recommends loading the roof rack only when
equipped with (optional) crossbars, to avoid unintended damage to the
roof panel.
WARNING: Loaded vehicles, with a higher center of gravity,
may handle differently than unloaded vehicles. Extra
precautions, such as slower speeds and increased stopping distance,
should be taken when driving a heavily loaded vehicle.
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 sport 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 increase risk of loss of vehicle control,
vehicle rollover, personal injury and death.
Driver Controls
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