freightliner cascadia, Driver Manual

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6.
Double-clutch between all upshifts and down-
shifts.
7. After your shifting ability improves, you may want
to skip some of the ratios. This may be done
only when operating conditions permit, depend-
ing on the load, grade, and road speed.
Upshifting
1. Position the gear shift lever in neutral. Start the
engine, and bring the air system pressure up to
100 to 120 psi (689 to 827 kPa).
2.
Position the range preselection lever down, into
low range.
3. Press the clutch pedal to the floor; shift into low
or 1st gear (
Table 14.1 ), then engage the clutch,
with the engine at or near idle speed, to start the
vehicle moving. Accelerate to 80 percent of en-
gine governed speed.
Eaton Fuller Shift Progressions
TRANS.
MODEL
LOW RANGE
HIGH
RANGE
Off-Highway On-Highway
10-Speed
Direct or
Overdrive
(RT or
RTX)
2
3
4
1
f260329
R
5
2
3
4
1
f260329
R
5
9
8 10
7
f260330
R
6
Table 14.1, Eaton Fuller Range-Shift Shift
Progressions
4. Shift progressively upward from low or 1st gear,
to the top gear in low range (
Table 14.1 ),
double-clutching between shifts, and accelerating
to 80 percent of engine governed speed.
5.
While in the top gear of the low range shift pat-
tern, and ready for the next upshift, flip the range
preselection lever up into high range. Double-
clutch through neutral, and shift into the bottom
gear in high range (
Table 14.1 ). As the shift lever
passes through neutral, the transmission will au-
tomatically shift from low range to high range.
6. With the transmission in high range, shift pro-
gressively upward through each of the high
range gears (
Table 14.1 ), double-clutching be-
tween shifts.
Downshifting
1. With the transmission in high range, shift pro-
gressively downward to the bottom gear in high
range, double-clutching between shifts.
2. When in the bottom gear of the high range shift
pattern, and ready for the next downshift, push
the range preselection lever down into low range.
Double-clutch through neutral, and shift into the
top gear of the low range shift pattern. As the
shift lever passes through neutral, the transmis-
sion will automatically shift from high range to
low range.
3. With the transmission in low range, downshift
through the low range gears as conditions re-
quire.
IMPORTANT: Never use the clutch brake when
downshifting, or as a brake to slow the vehicle.
Clutch
General Information
The hydraulic clutch control system consists of a
pedal unit and a slave cylinder, connected by a hy-
draulic hose and fastened with quick-disconnect
clamps. The components of the system have been
specially designed to use DOT 4 brake fluid. The
pedal unit includes a hydraulic subassembly, com-
posed of the master cylinder and reservoir, which
can be removed from the pedal unit for service pur-
poses. When the clutch pedal is depressed, the fluid
in the master cylinder is forced through a hydraulic
line to the slave cylinder. The fluid pressure moves
the slave cylinder piston, pushing the plunger rod
and clutch release lever, which disengages the
clutch. The hydraulic system is self-adjusting.
Clutches are designed to absorb and dissipate more
heat than encountered in typical operation. The tem-
peratures developed in typical operation will not
break down the clutch friction surfaces. However, if a
clutch is slipped excessively, or asked to do the job
of a fluid coupling, high temperatures develop quickly
and destroy the clutch. Temperatures generated be-
tween the flywheel, driven discs, and pressure plates
can be high enough to cause the metal to flow and
the friction facing material to char and burn.
Heat and wear are practically nonexistent when a
clutch is fully engaged. But during the moment of
engagement, when the clutch is picking up the load,
Manual Transmissions and Hydraulic Clutch
14.5