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Use the trailer brake hand control to help avoid jackknifing. This control will apply the
trailer brakes only. To apply the trailer brakes, pull down on the control. Be sure to
return the control to its off position (all the way up) when you have finished using it.
USING THE INTERAXLE DIFFERENTIAL LOCKUP
Interaxle differential lockup provides additional traction by applying full torque to both
rear axles. This feature should be used any time tractive conditions are poor, e.g., rainy
or icy pavement.
The Differential Lock/Unlock control is located on the instrument panel to the right
of the driver. Use the following instructions to engage and disengage the system.
Engage:
1. Pull to the side of the road and stop the truck, but leave engine running.
2. Place the Differential Lock/Unlock control in the LOCK position.
3. Observe that the Differential Lockout indicator lamp comes on. The truck is now
ready for operation.
Disengage:
1. Remove your foot from the accelerator pedal.
2. Place the Differential Lock/Unlock control in the UNLOCK position.
3. Observe that the Differential Lockup indicator lamp goes off. The system is now
disengaged.
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