Ford F-650 2008 User Manual page 127

Shifting the axle from HI to LO range - vehicle stopped
Place the transmission in N (Neutral), then press the upper part of the
switch.
Note: Do not shift the axle to LO range with the vehicle in motion.
Split-shifting (combined axle and transmission shift - manual
transmissions only)
Ratio 1 2
combination
Transmission 1st 1st
gear
Axle range LO HI
To downshift the axle to a slower ratio and shift the transmission, shift
the transmission and move the control switch to the lower ratio before
the clutch is re-engaged.
To upshift the axle and shift the transmission, move the control switch
to a faster ratio and make the transmission shift in the usual manner.
Ratio extender use
Low End
A two-speed axle can be used as a ratio-extender when split shifting is
not necessary. For low end use, just shift the axle into LO to start out,
and shift to HI when the extra torque is no longer needed.
Transmission (5-speed)
Two-speed axle
High End
To use the two-speed axle as a high end ratio-extender, stay in the LO
range for normal upshifts and only shift the axle to HI on the freeway for
greater road speed.
Transmission
(5-speed)
Two-speed axle
2008 F-650/750 (f67)
Supplement
Split-shift sequence
3 4 5 6 7
2nd 2nd 3rd 3rd 4th 4th 5th 6th 6th
LO HI LO HI LO
1st 1st 2nd 3rd 4th 5th 6th
Axle low
1st 2nd 3rd
Low for gradeability
Driving
8 9 10 11
HI LO LO HI
Axle high
4th 5th 6th
Speed
Axle high
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