Using The All-Wheel Drive (Awd) System - Ford 2008 F-150 Owner's Manual

normal and should be no reason for concern. Refer to Shifting to/from
4L (4WD Low) for proper operation.
Shifting between 2H (2WD High) and 4H (4WD High)
Move the 4WD control between 2H and 4H at any forward speed up to
55 mph (88 km/h).
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.
Shifting to/from 4L (4WD Low)
1. Bring the vehicle to a complete stop
2. Place the transmission in N (Neutral).
3. Move the 4WD control to the desired position.
If shifting into 4L (4WD Low), wait for the 4X4 LOW light in the
instrument cluster to turn on indicating the shift is complete.
If shifting out of 4L (4WD Low), wait for the 4X4 LOW light in the
instrument cluster to turn off indicating the shift is complete.
Note: Some noise may be heard as the system shifts or engages; this is
normal.

Using the all-wheel drive (AWD) system

(if equipped, Harley-Davidson and Limited only)
This system includes an electronically controlled transfer case. The
system is interactive with the road, continually monitoring and adjusting
torque delivery to the front and rear wheels to optimize traction.
AWD (Auto) - Power delivered to all four wheels, as required, for
increased traction. This is appropriate for all on-road driving conditions,
such as dry road surfaces, wet pavement, snow, gravel and shallow sand.
2008 F-150
Owners Guide (post-2002-fmt)
USA
Driving
285