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OPERATION 155
As grades and vehicle weight increase, it will be necessary to use the HIGH
position.
C0029332
1. High
3. Off
2. Low
Descending a Grade
DANGER
The MACK PowerLeash™ Engine Brake assists you in establishing faster
downhill descent speeds than in a similarly configured and loaded vehicle without
an engine brake; nevertheless, even with an engine brake, there are limits to the
maximum vehicle speed at which you can travel on downhill grades and still
keep your vehicle safely under control. Always approach these situations with
caution, and gain the experience necessary for each grade and driving condition
to determine the appropriate downhill descent speed.
For a certain vehicle and load condition, a "control speed" may be established
for a given descent. The control speed is the vehicle speed at which the
retarding forces of air drag, rolling resistance and engine brake power are
equally balanced by the natural force of gravity that causes the vehicle to
accelerate down the hill, resulting in a steady, controlled vehicle speed. The
additional vehicle slowing power offered by the MACK PowerLeash™ Engine
Brake allows the driver to descend the hill in a higher gear than normal (at a
faster control speed), without overspeeding the engine.
For example, consider that you are descending a grade with a specific vehicle
and an assumed total vehicle weight. You will find that without an engine
brake, you must descend this grade in third gear to maintain a steady 10 mph
at 2,000 engine rpm, without the need to apply the service brakes.
Summary of Contents for Granite GU Series
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Page 44: ...SAFETY INFORMATION 33 Advisory Label Locations On Vehicle Labels Found on Chassis C0029831 ...
Page 45: ...34 SAFETY INFORMATION C0028958 ...
Page 46: ...SAFETY INFORMATION 35 C0028959 ...
Page 47: ...36 SAFETY INFORMATION C0029013 1 Right Side Frame Rail 2 Hood Prop ...
Page 48: ...SAFETY INFORMATION 37 C0029014 ...
Page 49: ...38 SAFETY INFORMATION Labels Found on Driver Side Sun Visor C0029832 ...
Page 50: ...SAFETY INFORMATION 39 C0029016 ...
Page 58: ...SAFETY INFORMATION 47 C0029833 ...
Page 60: ...SAFETY INFORMATION 49 C0029834 ...
Page 62: ...SAFETY INFORMATION 51 C0029835 ...
Page 72: ...INSTRUMENTS AND CONTROLS 61 Panel B W3056238 ...
Page 81: ...70 INSTRUMENTS AND CONTROLS C0029141 ...
Page 82: ...INSTRUMENTS AND CONTROLS 71 Diagnostics W3036575 W3036576 W3036583 ...
Page 84: ...INSTRUMENTS AND CONTROLS 73 C0029144 ...
Page 113: ...102 INSTRUMENTS AND CONTROLS C0029240 C0029241 ...
Page 235: ...224 OPERATION C0029351 ...
Page 241: ...230 OPERATION C0029352 ...
Page 284: ...MAINTENANCE AND LUBRICATION 273 C0029851 C0029852 1 Towhook Access ...
Page 305: ...294 MAINTENANCE AND LUBRICATION C0029434 1 Front 2 Back ...
Page 317: ......