USING TRAILER BRAKE HAND CONTROL

TM 9-2320-273-10

CAUTION

After use, always return the trailer brake hand control to

its off position (all the way up), or the trailer brakes will

burn up.

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

CAUTION

Do not operate the truck on hard surfaces any longer

than necessary with the differential lockup engaged.

Otherwise driveline windup can occur which can damage

the differential.

Interaxle differential lockup provides additional traction by applying full torque to

both rear axles. On M916 through M920 models, the front driving axle is also engaged.

This feature should be used any time tractive conditions are poor, e.g., rainy or icy

pavement. For M916 through M920 models, it should also be used in off-road oper-

ations.

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 (All Models)

1. Pull to the side of the road and stop the truck.

2. Place the Differential Lock/Unlock control in the LOCK position.

3. Observe that the Differential Lockout indicator light comes on. The truck is now

ready for operation.

Disengage

M915 Only

1. Remove your foot from the accelerator pedal.

2. Place the Differential Lock/Unlock control in the UNLOCK position.