FORD 2015 F-550 v.1 - Manual (Page 154)

USING FOUR-WHEEL DRIVE
WARNING
For important information regarding
safe operation of this type of vehicle,
See General Information (page
263).
Note: Do not use 4X4 mode on dry, hard
surfaced roads. Doing so will produce
excessive noise, increase tire wear and may
damage drive components. 4X4 mode is
only intended for consistently slippery or
loose surfaces.
Note: If 4X4 low is selected while the
vehicle is moving above 3 mph (5 km/h),
the 4WD system will not perform a shift.
This is normal and should be no reason for
concern. Refer to Shifting to/from 4L (4X4
Low) for proper operation.
Manual Shift On Stop (MSOS)
4WD system
(If Equipped)
Note: Some vehicles may be equipped with
wheel ornaments that cover the 4x4 manual
hub lock. These ornaments must be
removed to access the manual hub locks.
Note: The vehicle should not be driven in
4X4 High or 4X4 Low modes with the hub
locks set to FREE as this condition may
damage driveline system components.
LOCK
E E R F
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The 4WD system is engaged or disengaged
by rotating the control for both front wheel
hub locks from the FREE or LOCK position,
then manually engaging or disengaging the
transfer case with the floor-mounted
shifter. For increased fuel economy in 2WD,
rotate both hub locks to the FREE position.
Electronic Shift-On-the-Fly
(ESOF) 4WD system
Note: If 4X4 Low is selected while the
vehicle is moving above 3 mph (5 km/h),
the 4WD system will not perform a shift.
This is normal and should be no reason for
concern. Refer to Shifting to/from 4L (4X4
Low) for proper system operation.
Note: Auto-manual hub locks can be
manually overridden by rotating the hub lock
control from AUTO to LOCK.
LOCK
O T U A
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For proper operation, make sure that each
hub is fully engaged and that both hub
locks are set to the same position (both
set to LOCK or both set to AUTO). To
engage LOCK, turn the hub locks
completely clockwise; to engage AUTO,
turn the hub locks completely
counterclockwise.
The ESOF 4WD system:
151
Super Duty (), enUSA
Four-Wheel Drive
(If Equipped)