FORD 1999 Explorer - Manual (Page 13)

diagonally up or down a hill or
steep incline, you should always
try to drive straight up or straight
down. Avoid driving crosswise
or turning on steep slopes or
hills. A danger lies in losing
traction, slipping sideways and
possibly rolling over. Whenever
driving on a hill, determine
beforehand the route you will use.
Do not drive over the crest of a hill
without seeing what conditions are
on the other side. Do not drive in
reverse over a hill without the aid
of an observer.
When climbing a steep slope or
hill, start in a lower gear rather
than downshifting to a lower gear
from a higher gear once the ascent
has started. This reduces strain on
the engine and the possibility of
stalling.
If you do stall out, Do not try to
turnaround because you might roll
over. It is better to back down to a
safe location.
Apply just enough power to the
wheels to climb the hill. Too much
power will cause the tires to slip,
spin or lose traction, resulting in
loss of vehicle control.
Driving off-road with 4WD or AWD
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