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STARTING AND OPERATING
CONTENTS
mStarting Procedures ± Diesel Engines.........268
NAutomatic Transmission ± If Equipped......268
NManual Transmission ± If Equipped........269
NNormal Starting Procedure ± Engine Manifold
Air Temperature Above 66ÉF (19ÉC)........269
NStarting Procedure ± Engine Manifold Air
Temperature Below 66ÉF (19ÉC)...........270
NStarting Fluids.......................274
mNormal Operation (Diesel Engine)...........274
NCold Weather Precautions...............275NEngine Idling........................278
NStopping The Engine...................280
NEngine Speed Control..................281
NOperating Precautions..................281
NCooling System Tips Ð Automatic
Transmission........................281
mDiesel Exhaust Brake (Engine Braking) ±
If Equipped...........................283
mTransmission Shifting....................285
NAutomatic Transmission With Overdrive
(68RFE) Ð If Equipped.................285
5
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Stopping The Engine
Idle the engine a few minutes before routine shutdown.
After full load operation, idle the engine 3 to 5 minutes
before shutting it down. This idle period will allow the
lubricating oil and coolant to carry excess heat away from
the combustion chamber, bearings, internal components,
and turbocharger. This is especially important for turbo-
charged, charge air cooled engines.
NOTE:During engine shutdown on vehicles equipped
with manual transmissions, it is normal for the diesel
engine to resonate heavily for a moment during engine
shut off. When the engine is connected to a manual
transmission, this resonance causes loud gear rattle from
the transmission. This is commonly referred to as ªshut
down rattleº. The manufacturer recommends performing
engine shut down with the clutch pedal pushed to the
floor (clutch disengaged). When engine shut down is
performed in this manner the rattle is reduced (not
eliminated).Driving
ConditionLoadTurbo-
charger
TemperatureIdle Time
(min.) Be-
fore Engine
Shutdown
Stop and
GoEmpty Cool Less than
One
Stop and
GoMedium One
Highway
SpeedsMedium Warm Two
City Traffic Maximum
GCWRThree
Highway
SpeedsMaximum
GCWRFour
Uphill
GradeMaximum
GCWRHot Five
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Engine Speed Control
CAUTION!
Prevent overspeeding the engine going down hill.
When descending steep grades, use a combination of
gears and service brakes to control vehicle/engine
speed. Overspeed can cause severe engine damage.
Operating Precautions
Avoid Overheating The Engine
The temperature of the coolant (a mixture of 50%
ethylene-glycol and 50% water) must not exceed the
normal range of the temperature gauge (240ÉF/116ÉC)
with a 16 psi (110 kPa) radiator cap.
Usually the coolant temperature indicated during opera-
tion will be to the left of center in the normal range of the
gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low coolant temperature below
the normal range on the gauge (140ÉF/60ÉC) can be
harmful to the engine. Low coolant temperature can
cause incomplete combustion which allows carbon and
varnish to form on piston rings and injector nozzles.
Also, the unburned fuel can enter the crankcase, diluting
the lubricating oil and causing rapid wear to the engine.
Cooling System Tips Ð Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
²City Driving Ð
when stopped, put transmission in neutral and increase
engine idle speed.
²Highway Driving Ð
reduce your speed.
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WARNING!
Your vehicle could move and injure you and others if
it is not completely in PARK. Check by trying to
move the shift lever back and forth without first
pulling it toward you after you have set it in PARK.
Make sure it is in PARK before leaving the vehicle.
WARNING!
It is dangerous to shift the shift lever out of PARK or
NEUTRAL if the engine speed is higher than idle
speed. If your foot is not firmly on the brake pedal,
the vehicle could accelerate quickly forward or in
reverse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when the
engine is idling normally and when your right foot is
firmly on the brake pedal.REVERSE
Use this range only after the vehicle has come to a
complete stop.
NEUTRAL
Shift to NEUTRAL when the vehicle is standing for
prolonged periods with the engine running. The engine
may be started in this range. Set the parking brake if you
must leave the vehicle.
DRIVE
Drive range provides underdrive 1st, 2nd and 3rd gears,
direct 4th gear and overdrive 5th and 6th gears. The shift
into overdrive 5th and 6th gear occurs only after the
transmission has completed the shift into 4th gear. No
other movement of the shift mechanism is required to
complete the 4±5 or 5±6 gear shifts.
The 4th and 5th gear upshifts occurs automatically unless
the Tow/Haul mode is enabled.
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Maximum Recommended Downshifting Speeds
Gear
Selec-
tion6to5 5to4 4to3 3to2 2toL
Maxi-
mum
Speed68 mph
(109
km/h)50 mph
(80
km/h)32 mph
(51
km/h)19 mph
(31
km/h)10 mph
(16
km/h)
Reverse Shifting
To shift into REVERSE (R), bring the vehicle to a com-
plete stop. Depress the clutch and pause briefly to allow
the gear train to stop rotating. Beginning from the
NEUTRAL (N) position, move the shift lever in one quick
smooth motion straight across and into the REVERSE (R)
area (the driver will feel a firm ªclickº as the shifter
passes the ªknock-overº). Complete the shift by pulling
the shift lever into REVERSE (R).
The ªknock-overº prevents the driver from accidentally
entering the REVERSE (R) shift area and warns the driverthat they are about to shift the transmission into RE-
VERSE (R). Due to this feature, a slow shift to REVERSE
(R) can be perceived as a high shift effort.
To shift out of reverse bring the vehicle to a complete stop
and depress the clutch. Shifting out of reverse prior to a
complete stop may cause high shift effort.
FOUR±WHEEL DRIVE OPERATION Ð IF
EQUIPPED
Four-Wheel Drive trucks are equipped with either a
manually shifted transfer case or an electronically shifted
transfer case. See the operating instructions for your
transfer case, located within this section.
Manually Shifted Transfer Case Operating
Information/Precautions
The transfer case provides 4 mode positions-2(rear)-
wheel drive high range, 4-wheel drive high range, neu-
tral, and 4-wheel drive low range.
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This transfer case is intended to be driven in the 2-wheel
drive position (2H) for normal street and highway con-
ditions such as dry hard surfaced roads.
When additional traction is required the transfer case 4H
and 4L positions can be used to lock the front and rear
driveshafts together and force the front and rear wheels
to rotate at the same speed. This is accomplished by
simply moving the shift lever to the desired positions.
The 4H and 4L positions are intended for loose, slippery
road surfaces only. Driving in the 4H and 4L positions on
dry hard surfaced roads may cause increased tire wear
and damage to the driveline components.
The 4-wheel drive light (4WD), located in the instrument
cluster, alerts the driver that the vehicle is in 4-wheel
drive and that the front and rear driveshafts are locked
together. This light illuminates when the transfer case is
shifted to either the 4H or 4L positions. There is no light
for the 2H or NEUTRAL positions.When operating your vehicle in 4L, the engine speed is
approximately three times that of the 2H or 4H positions
at a given road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).
Proper operation of 4-wheel drive vehicles depends on
tires of equal size, type and circumference on each wheel.
Any difference will adversely affect shifting and can
cause damage to the transfer case.
NOTE:Do not attempt to make a shift while only the
front or rear wheels are spinning. The transfer case is not
equipped with a synchronizer and therefore the front and
rear driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case.
Because 4-wheel drive provides improved traction, there
is a tendency to exceed safe turning and stopping speeds.
Do not go faster than road conditions permit.
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4L
4-Wheel Drive Low Range - Low speed 4-wheel drive.
Locks the front and rear driveshafts together. Forces the
front and rear wheels to rotate at the same speed.
Additional traction and maximum pulling power for
loose, slippery road surfaces only. Do not exceed 25 mph
(40 km/h).
Shifting Procedure - Manually Shifted Transfer
Case
2H,4H
Shifting between 2H and 4H can be made with the
vehicle stopped or in motion. If the vehicle is in motion,
shifts can be made up to 55 mph (88 km/h). With the
Manual Transfer Case Shifter
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vehicle in motion, the transfer case will engage/
disengage faster if you momentarily release the accelera-
tor pedal after completing the shift. Apply a constant
force when shifting the transfer case lever.
2H or 4H,4L
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift
an automatic transmission to NEUTRAL or depress the
clutch on a manual transmission. While the vehicle is
coasting at 2 to 3 mph (3 to 5 km/h), shift the transfer
case lever firmly to the desired position. Do not pause in
transfer case NEUTRAL.
NOTE:Pausing in transfer case NEUTRAL in vehicles
equipped with an automatic transmission may require
shutting the engine OFF to avoid gear clash while
completing the shift. If difficulty occurs, shift automatic
transmission to NEUTRAL, hold foot on brake, and turn
engine OFF. Make shift to the desired mode.NOTE:Shifting into or out of 4L is possible with the
vehicle completely stopped, however difficulty may oc-
cur due to the mating clutch teeth not being properly
aligned. Several attempts may be required for clutch
teeth alignment and shift completion to occur. The pre-
ferred method is with the vehicle rolling 2 to 3 mph (3 to
5 km/h). Avoid attempting to engage or disengage 4L
with the vehicle moving faster than 2 to 3 mph (3 to 5
km/h).
NOTE:Do not attempt to shift to or from 4L while the
transmission is in gear or clutch is engaged.
Transfer Case Reminder Light
The four-wheel drive operating light (4WD), located in
the instrument cluster, is used to alert the driver that the
front axle is fully engaged and all four wheels are
driving.
298 STARTING AND OPERATING