FORD 2002 F-550 v.2 - Manual (Page 138)

If your vehicle gets stuck in mud or snow it may be rocked out by
shifting from forward and reverse gears, stopping between shifts, in a
steady pattern. Press lightly on the accelerator in each gear.
Do not rock the vehicle for more than a few minutes. The
transmission and tires may be damaged or the engine may
overheat.
Always set the parking brake fully and make sure the gearshift is
latched in P (Park). Turn the ignition to the LOCK position and
remove the key whenever you leave your vehicle.
If the parking brake is fully released, but the brake warning lamp
remains illuminated, the brakes may not be working properly.
See your dealer or a qualified service technician.
Driving with a 4–speed automatic transmission
Understanding gearshift positions
To put your vehicle in gear, start the engine, depress the brake pedal,
then move gearshift lever out of P (Park).
Hold the brake pedal down while you move the gearshift lever
from P (Park) to another position. If you do not hold the brake
pedal down, your vehicle may move unexpectedly and injure someone.
P (Park)
Always come to a complete stop
before shifting into P (Park). Make
sure the gearshift lever is securely
latched in P (Park). This position
locks the transmission and prevents
the rear wheels from turning.
Always set the parking brake fully and make sure the gearshift
lever is latched in P (Park). Turn off the ignition whenever you
leave your vehicle.
Driving
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