Ford F-150 2010 Owner's Manual page 303

Note: Momentarily releasing the accelerator pedal while performing a
shift will improve engagement/disengagement times.
Note: Do not perform this operation if the rear wheels are slipping.
Note: Some noise may be heard as the system shifts or engages; this is
normal.
Note: 4X4 high mode is not intended for use on dry pavement.
Shifting to/from 4L (4X4 low)
1. Bring the vehicle to a speed of 3 mph (5 km/h) or less.
2. Place the transmission in N (Neutral).
3. Move the transfer case lever through N (Neutral) directly to the
desired position.
• If the transfer case will not engage into 4L (4X4 low) do not force
the lever. Allow the vehicle to coast at a speed below 3 mph
(5 km/h), then repeat Steps 2 and 3.
Note: Some noise may be heard as the system shifts or engages; this is
normal.
Note: 4X4 low mode is not intended for use on dry pavement.
Note: For proper operation in 4X4 low, ensure the transfer case shift
lever is moved entirely rearward in to the 4L (4X4 Low) position and
that the 4x4 Low light is displayed in the message center.
Note: Ideal 4L (4X4 low) shift conditions occur when the vehicle is
rolling at a speed below 3 mph (5 km/h) and the transmission is in N
(Neutral).
Using the N (Neutral) position
The transfer case N (Neutral) position overrides the transmission
and puts the vehicle in neutral regardless of transmission
gearshift lever position. The vehicle can move forward or
backward.
This position should only be used when towing the vehicle.
WARNING: Do not leave the vehicle unattended with the
transfer case in the N (Neutral) position. Always set the parking
brake fully and turn off the ignition when leaving the vehicle.
Driving
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