Operating On Flat, Dry Pavement; Operating Down A Long, Steep Grade - Detroit Diesel DD15 EuroIV Operator's Manual

Anti-Lock Braking Systems
Vehicles equipped with ABS have the ability to turn the engine brake OFF if a
wheel-slip condition is detected. The engine brake will automatically turn itself ON
once the wheel slip is no longer detected.
The DDEC system will deactivate the engine brake system when the engine speed
falls below a preset rpm or when the vehicle slows down to a preset speed,
depending on DDEC programming. This prevents stalling the engine. The engine
brake can also be used with vehicle Cruise Control turned ON.

Operating on Flat, Dry Pavement

Use the following guidelines when driving on flat, dry pavement:
• If driving on flat, dry, open stretches with a light load and greater slowing power
is not required, place the progressive braking switch in the LOW position.
• If you find you are still using the service brakes, move the progressive braking
switch to a higher position until you do not need to use the service brakes to slow
the vehicle down.
• If you are carrying a heavier load and road traction is good, move the progressive
braking switch to the HIGH position.
• Check your progressive braking switch often for proper position, since road
conditions can change quickly. Never skip a step when operating the progressive
braking switch. Always go from OFF to LOW, and then to a higher position.

Operating Down a Long, Steep Grade

An explanation of speed; may be helpful in understanding how to use the engine
brake system while descending a grade. Control Speed is the constant speed at
which the forces pushing the vehicle forward on a grade are equal to the forces
holding it back, without using the vehicle service brakes. In other words, this is the
speed the vehicle will maintain without using the service brakes or fueling.
NOTICE: Failure to keep the vehicle within safe control speed limits while
descending a grade may result in vehicle or property damage or both.
Use the following guidelines when descending a long, steep grade:
1. Before beginning the descent, determine if your engine brake system is
operating properly by lifting your foot briefly off the accelerator pedal. You
should feel the system activate.
All information subject to change without notice.
DDC-SVC-MAN-0175 Copyright © 2014 DETROIT DIESEL CORPORATION
DD Platform EuroIV Operators Manual
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