Specifications

CONTROLS AND DISPLAY DASH- AND DOOR-MOUNTED FEATURES
Medium Duty
(R05/09) Y53-6008A – 59 –
Jacobs Engine Brake or Cummins “C” Brake
Switch
The ON/OFF switch turns the system ON or OFF. The
second switch performs the progressive braking function
that controls the amount of retarding.
• If you have the two-mode system, you can select
HIGH or LOW.
• If you have the three-mode system, you can select
low, medium, or high retarding.
Interaxle Differential Lock Switch
The interaxle differential allows differential action between
the forward rear and the rear rear driving axles. The inter-
axle differential lock switch allows the operator to LOCK or
UNLOCK the differential. The guard over this switch pre-
vents you from accidentally activating the lock.
2-Mode and 3-Mode Systems
SHIFT AT ANY SPEED EXCEPT
IF A WHEEL IS SPINNING