Manual Transmission - PREVOST Motorcoach XL Series Operator's Manual

CAUTION
: Detroit Diesel engines should not be
idled for extended periods at "low" idle.
extended idling, engine should run at "fast" idle.
WARNING:
Always apply parking brake before
leaving driver's seat.
Do not allow your vehicle to "coast" in Neutral.
This practice can result in transmission damage.
Also, no engine braking is available in Neutral.
C) Drive (D)
Use this position for all normal driving conditions.
After touching this pad, the vehicle will start in first
or second range and will automatically upshift to a
higher range as output speed increases. As the
vehicle slows down, output speed decreases, and
the transmission automatically downshifts to the
correct range. If a locked brake or a slick surface
condition should occur, the ECU (Electronic
Control Unit) will command converter operation
(disconnect lockup) and inhibit downshifts for a
period of time or until normal wheel speed has
been restored.
NOTE:
The transmission should normally be
allowed to shift itself, but manual shifting can be
used as described below.
D) Fourth (4) and Third (3) ranges
Select these ranges when driving on moderate
grades, or when load and traffic conditions require
the use of limited speed.
E) Second (2) range
Select this range when operating in heavy and
congested traffic. The transmission will start in
first and automatically upshift to second. When
slowing, the transmission
downshift to first range.
progressively greater engine(*) and retarder(*)
braking power (the lower the range, the greater
the engine(*) and retarder(*) braking effect).
F) First (1) range
Select this range when pulling through mud and
snow, or when speed control is needed for driving
up steep grades. This range also provides
maximum engine(*) braking power or retarder(*)
braking effect. In the lower ranges (1, 2, 3, and
4), transmission will not upshift above the highest
gear selected unless recommended engine
governed speed for that gear is exceeded.
For
will automatically
Low ranges provide
CAUTION:
Service brakes (foot pedal) should
not be used to control the speed of vehicle on
long, steep descents. Instead, lower transmission
ranges should be used (in conjunction with output
retarder(*)). When descending in lower ranges,
care must be taken that engine speed does not
exceed 2450 rpm. This procedure keeps service
brakes cool and ready for emergency stopping.
- (*) - Refers to "JACOBS engine brake" and
"Transmission output retarder" options.
See pages 4-3 & 4-4 for details regarding
both systems.

MANUAL TRANSMISSION

6 OR 7-SPEED
The manual transmission has 6 or 7 forward
speeds (including creeper) and one reverse.
NOTE:
A Spicer PS145-7A, 7-speed trans-
mission, is specified with the 12.7 liter, series-60,
400-horsepower
6-speed, is specified with the optional 11.1 liter,
325-horsepower engine.
FIGURE 27
The transmission shift lever located to the right of
the driver's seat is used to select gears. The
coach is equipped with a safety switch to prevent
accidental starter engagement if the shift lever is
not in the neutral position.
When shifting from neutral to first or reverse gear,
depress the clutch pedal fully to activate the clutch
brake. This makes it easier to shift from neutral to
forward or reverse.
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CONTROLS/INSTRUMENTS
engine and a PS130-6B,
07008