FORD 2002 F-550 v.2 - Manual (Page 151)

Do not leave the vehicle unattended with the transfer case in the
N (Neutral) position. Always set the parking brake fully and turn
off the ignition when leaving the vehicle.
Using the electronic shift 4WD system (if equipped)
Positions of the electronic shift system
To prevent damage, the electronic shift 4WD system is designed
to allow up to 45 seconds before a shift command is performed.
In the event that conflicting shift commands are selected, allow
up to 45 seconds for the shift command to be performed prior to
reporting any shift concerns to your dealer.
2H (2WD High) – For general on-road driving. Sends power to the rear
wheels only.
4H (4WD High) – For winter and off-road conditions. Sends power to
front and rear wheels.
4L (4WD Low)– For low-speed off-road cond applications that require
extra power such as steep grades, deep sand or pulling a boat out of the
water. Sends power to front and rear wheels.
Note: Some noise may be heard as the 4WD system shifts or engages.
This is normal.
Shifting from 2WD (2WD High) to 4x4 HIGH (4WD High)
Rotate the 4WD control to the 4x4
HIGH position at speeds up to 88
km/h (55 mph).
• To prevent damage, the
electronic shift 4WD system is
designed to engage 4x4 HIGH
(4WD High) when the vehicle
is moving. If shifted to 4x4
HIGH (4WD HIGH) while at
complete stop, 4x4 may not
engage and the 4x4 indicator
may not illuminate until the vehicle is driven above 8 km/h
(5 mph).
Do not shift into 4x4 HIGH with the rear wheels slipping.
4X4
HIGH
2WD
4X4
LOW
Driving
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