Navistar WorkStar Series, Operator'S Manual

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Operation
NOTE: Ensure that the wheels are not slipping while performing
these steps, and that there are no error conditions or indicators
displayed.
1. The vehicle must first be operating on a level surface.
2. Slow the vehicle to a speed below 10 miles per hour.
3. Place the ON/FRONT AXLE switch in the FRONT AXLE
(Off) position.
4. The front axle will disengage and the indicator will go
out.
Shifting Transfer Case From High to Low or Low to High
Gear Ratio
The system will only allow the transfer case to be shifted
to the low gear ratio if the following steps are performed:
NOTE: Ensure that there are no error conditions or
indicators displayed.
1. The vehicle must be stopped and the parking
brake applied (Ignition switch still in the ‘run’
position).
2. Place the transmission in Neutral.
3. Place the XFER HI/XFER LOW switch in the XFER HI
position for the high gear ratio or XFER LOW position
for the low gear ratio.
Front Axle Engagement and Transfer Case Gear Ratio
Shifting with Vehicle Stopped
The transfer case gear ratio can be selected and the front axle
can be engaged at the same time by performing the following
steps:
NOTE: Ensure that there are no error conditions or indicators
displayed.
1. The vehicle must be stopped and the parking brake
applied (Ignition switch still in the ‘run’ position).
2. Place the transmission in Neutral.
3. Place the ON/FRONT AXLE switch in the ON position.
4. The front axle will be engaged and the indicator will be
lit.
5. Place the XFER HI/XFER LOW switch in the position
required for the desired gear ratio.
Vehicles with Transfer Case Oil Temp(erature) Sender
CAUTION
To prevent damage to transfer case, pull vehicle
off the road immediately when overheating
condition is detected.
If the transfer case lubricant exceeds its maximum allowable
temperature, damage to the transfer case may result. If this
occurs, the transfer case overheat indicator will be lit, alerting
the driver. In the event of a transfer case overheating condition,
proceed with the following:
1. Pull off the highway as soon as possible.
2. Inspect the transfer case and cooling system for leaks.
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