Ford F-250 Super Duty (1999 year). Manual — part 32

FOUR-WHEEL DRIVE (4WD) OPERATION (IF EQUIPPED)

When Four–wheel drive (4WD) is engaged, power is supplied to all four
wheels through a transfer case. 4WD power can be selected when
additional driving power is desired.

If equipped with the Electronic Shift 4WD System, and the
instrument panel control is moved to 4WD Low while the vehicle
is moving, the system will not engage and no damage will occur to
the 4WD system.

All utility-type vehicles and 4WD vehicles have special design and
equipment features to make them capable of performing in a wide
variety of off-road applications. Specific design characteristics give them
higher centers of gravity than ordinary passenger cars.

Utility and four-wheel drive vehicles are not designed for
cornering at speeds as high as passenger cars any more than

low-slung sports cars are designed to perform satisfactorily under
off-road conditions. Avoid sharp turns or abrupt maneuvers in these
vehicles.

4WD operation is not recommended on dry pavement. Doing so could
result in difficult disengagement of the transfer case, increased tire wear
and decreased fuel economy.

Electronic shift on the fly (ESOF) 4x4 system (if equipped)

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 hub locks that can be engaged and disengaged automatically by

using a rotary control located on the instrument panel.

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• automatic hub locks can be

manually overridden by rotating
the hub lock control from AUTO
to LOCK.

Manual 4x4 system (if equipped)

The 4WD system is engaged or
disengaged by rotating the front
wheel hub lock control from FREE
to LOCK, then manually engaging
the transfer case with a
floor-mounted shifter.

4WD system indicator lights

The 4WD system indicator lights illuminate only under the following
conditions. If these lights illuminate during normal driving, have your
vehicle serviced.
• 4x4 -illuminates when the

ignition is turned on and when
4H (4x4 High) is selected.

• LOW RANGE –illuminates when

the ignition is turned on or when
4L (4x4 Low) is selected.

Using a manual 4WD system (if equipped)

2H (2WD High) – Power to rear axle only.

4H (4WD High) – Power to front and rear axles.

N (Neutral) – No power to either axle.

4L (4WD Low) – Power to front and rear axles at reduced speed.

4x4

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Shifting from 2H (2WD high) to 4H (4WD high)

Engage the locking hubs by rotating
the hub lock control from FREE to
LOCK, then move the transfer case
lever from 2H (2WD High) to 4H
(4WD High).

Do not shift into 4H (4WD High)
with the rear wheels slipping.

Shifting from 4H (4WD high) to 2H (2WD high)

Move the transfer case lever to 2H
(2WD High) at a stop or any
forward speed up to 88 km/h (55
mph).

With the vehicle at complete stop,
disengage the locking hubs
(optional) by rotating the hub lock
control from LOCK to FREE.

Shifting from 4H (4WD high) to 4L (4WD low)

1. Bring the vehicle to a complete stop.

2. Depress the brake.

3. Place the gearshift lever in N (Neutral) (automatic transmission) or
depress the clutch (manual transmission).

2H
4H

4L

N

2H
4H

4L

N

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4. Move the transfer case shift lever
through N (Neutral) directly to 4H
(4WD High) or 4L (4WD Low).

Using the N (Neutral) position

The transfer case neutral position overrides the transmission and
puts the vehicle in neutral regardless of transmission gearshift
lever position. The vehicle can move forward or backwards.

This position should only be used
when towing the vehicle. Refer to
Wrecker towing in the Roadside
emergencies chapter.

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 the 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.

2WD (2WD High) – Power to rear axle only.

4x4 HIGH (4WD High) – Power delivered to front and rear axles for
increased traction.

4x4 LOW (4WD Low) – Power to front and rear axles at low speeds.

2H
4H

4L

N

2H
4H

4L

N

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