FORD 2004 F-150 v.1 - Manual (Page 185)

• Do not shift the transmission from a forward gear to R (Reverse) until
the engine is at idle and the wheels are stopped.
• 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.
Engine temperature while plowing
When driving with a plow, your engine may run at a higher temperature
than normal because the attached snowplow blade will restrict airflow to
the radiator.
If you are driving more than 24 km (15 miles) at temperatures above
freezing, angle the plow blade either full left or full right to provide
maximum airflow to the radiator.
If you are driving less than 24 km (15 miles) at speeds up to 64 km/h
(40 mph) in cold weather, you will not need to worry about blade
position to provide maximum airflow.
Driving
185