FORD 2002 Explorer v.1 - Manual (Page 188)

4x4 High and 4x4 Low operation is not recommended on dry
pavement. Doing so could result in difficult disengagement of the
transfer case, increased tire wear and decreased fuel economy.
Control-Trac automatic four-wheel drive system (if equipped)
The 4WD system uses all four wheels to power the vehicle. This
increases traction, enabling you to drive your 4x4 over terrain and road
conditions not normally traveled by two-wheel drive vehicles.
Power is supplied to all four wheels through a transfer case that allows
you to select a four-wheel drive mode best suited for your current
driving conditions.
Positions of the Control-Trac system
The Control-Trac system functions in three modes:
• The 4x4 Auto mode provides
four-wheel drive with full power
delivered to the rear axle, and to
the front axle as required for
increased traction. This is
appropriate for normal on-road
operating conditions, such as dry
road surfaces, wet pavement,
snow and gravel.
4X4
Low
4X4
High
4X4
Auto
Driving
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