FORD 2003 F-150 v.3 - Manual (Page 173)

• If the vehicle is stuck, shift the transmission in a steady motion
between forward and reverse gears. Do not rock the vehicle for more
than a few minutes. The transmission and tires may be damaged or
the engine can overheat.
Do not rock the vehicle if the engine is not at operating
temperature. Do not rock the vehicle for more than a minute. The
transmission and tires may be damaged or the engine may
overheat.
Do not spin the wheels at over 35 mph (55 km/h). The tires may
fail and injure a passenger or bystander.
Driving
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