FORD 2008 F-550 v.2 - Manual (Page 249)

engaged, the vehicle speed must be below 5 mph (8 km/h) with
the brake pedal depressed and the transmission in N (Neutral). If
your vehicle is equipped with a manual transmission, the clutch
pedal also must be depressed.This vehicle is equipped with a
non-synchronous low range gearset which will not allow the
transfer case to shift into 4X4 LOW if vehicle speed is above
5 mph (8 km/h). It is recommended that a shift to 4X4 LOW is
performed while the vehicle is rolling at a speed below 5 mph
(8 km/h).
The 4WD system:
• provides 4x4 High engagement and disengagement while the vehicle is
moving.
• is operated by a rotary control located on the instrument panel that
allows you select 2WD, 4x4 High or 4x4 Low operation.
• uses auto-manual hub locks that can be engaged and disengaged
automatically based on the 4x4 mode selected.
• auto-manual hub locks can be
manually overridden by rotating
the hub lock control from AUTO
to LOCK if desired.
• automatic operation of the
hub locks is recommended, and
will increase fuel economy
• 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.
4WD system indicator lights
The 4WD system indicator lights illuminate only under the following
conditions. If these lights illuminate when driving in 2WD, contact your
authorized dealer as soon as possible.
• 4x4 HIGH - momentarily
illuminates after the engine is
started. Illuminates when 4H (4x4
High) or 4L (4x4 Low) is
engaged.
4x4
HIGH
2008 F-250/350/450/550 (f23)
Owners Guide (post-2002-fmt)
USA (fus)
Driving
249