Ford 2007 F-650 Owner's Manual page 133

Driving
add-on axles are installed by others on the truck chassis which allow
operator control for weight transfer from other axles (i.e., air lift axles).
When operating a loaded vehicle, the driver must keep all
adjustable axles on the ground at all times, supporting their
share of the vehicle's load. Failure to do so can overload other axles,
tires, wheels, springs, steering components, brakes and frames,
resulting in early component failure, loss of vehicle control, possible
property damage and personal injury.
TWO-SPEED REAR AXLE (IF EQUIPPED)
A two-speed rear axle allows the driver to select a LO range for greater
pulling power and a HI range for greater road speed and fuel economy.
These ranges can also be used to provide additional steps between
transmission shifts when driving on steep grades and/or fuel economy
may be factors.
Note: Do not shift between ranges when the speed control is on.
Never shift a two-speed axle when descending a steep grade as
this may cause loss of vehicle control and result in personal injury.
Axle shifting
Manual transmissions:
• To downshift, select the next lower gear, release and depress the
accelerator pedal rapidly, or while holding the accelerator pedal down,
release and engage the clutch rapidly. Note: The clutch method is
recommended when driving at slower speeds.
• To upshift, keep the accelerator pedal down, select the next higher
gear, release the accelerator and pause until the axle upshifts. Note:
De-clutch for smoother axle upshifts when driving at slower speeds.
132
2007 F-650/750 (f67)
Supplement
USA (fus)