Operators Manual

Table Of Contents
Engine Brake System
The engine is equipped with an engine brake. Before operating the vehicle, you
must familiarize yourself with the engine brake system to obtain optimum benefit
from it. Engine brake control systems may vary slightly, depending on the engine
brake configuration and cab design. However, basic operator controls are similar
for all models.
Driver Control Switches
Vehicles with manual transmissions allow the driver to turn the engine brake on and
off and select a Low, Medium, or High level of braking.
EPA07 Engine
The "Low" setting on this switch activates braking on two cylinders, yielding
about one-third engine braking horsepower.
The "Medium" setting on this switch activates four cylinders, supplying about
two-thirds engine braking horsepower.
The "High" setting on this switch activates all six cylinders, providing full
engine brake horsepower.
EPA10/GHG14/GHG17 Engine
The "Low" setting on this switch activates braking on three cylinders, yielding
about one-third engine braking horsepower.
The "Medium" setting on the switch activates all six cylinders, supplying about
two thirds engine braking horsepower.
The "High" setting on the switch activates all six cylinders, supplying full engine
brake horsepower.
NOTE: There is very little difference in the exhaust sound when the EPA10/
GHG14/GHG17 engine brakes are activated in either the medium or high
position. The GHG17 platform engines will experience slightly different
engine brake logic provided by enhancements within CPC software.
Clutch Pedal and Throttle Position Controls
Engine brakes have two additional controls, one activated by the position of the
clutch pedal and the other activated by the position of the throttle. These controls
permit fully automatic operation of the engine braking system.
Engine Brake Activation Conditions
The engine braking system only permits fully automatic operation when the
following conditions are met:
DD Heavy Duty Platform Operators Manual
All information subject to change without notice. 77
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