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To shift into Reverse, come to a complete stop. Depress
the clutch and pause briefly to allow the gear train to
stop. Move the shift lever from the Neutral position
straight across and back into Reverse.
Never drive with your foot resting on the clutch pedal, or
attempt to hold the vehicle on a hill with the clutch pedal
partially engaged, as this will cause abnormal wear on
the clutch.
Recommended Vehicle Shift Speeds
To utilize your manual transmission efficiently for both
fuel economy and performance, it should be upshifted as
listed in recommended shift speed chart. Shift at the
vehicle speeds listed for acceleration. Earlier upshifts
during cruise conditions (steady speeds) will result in
increased fuel economy, and may be used as indicated.
Manual Transmission — 6 Speed (G56)
2500 and 3500 models are equipped with the G56 manual
transmission. This transmission has a “creeper” 1st gear which should be used to start from a standing position
when carrying a payload or towing a trailer. Damage to
the clutch can result from starting in 2nd or 3rd gear with
a loaded vehicle. An unloaded vehicle may be launched
in 2nd gear. Use each gear in numerical order – do not
skip a gear.
For most city driving you may find it easier to use only
1st through 5th gear ranges. For steady highway driving
with light accelerations, 6th gear is recommended. To
shift into 5th gear, move the shift lever to the right
beyond the spring pressure point and push it forward.
When shifting from 5th to 4th gear, pull the lever down
toward you in one motion. Do not pull the lever sharply
left as you may shift accidentally into 2nd gear and
damage the transmission.
To shift into Reverse, come to a complete stop. Depress
the clutch and pause briefly to allow the gear train to
stop. Reverse has a “crash-through” lockout feature.
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To shift into Reverse, come to a complete stop. Depress
the clutch and pause briefly to allow the gear train to
stop. Reverse has a “crash-through” lockout feature.
Move the shift lever from the Neutral position straight
across, in one swift motion, and down into Reverse.
Recommended Shift Speeds
To use your manual transmission for fuel economy it
should be upshifted as listed below. Shift at the vehicle
speeds listed for acceleration. Earlier upshifts during
cruise conditions (relatively steady speeds) will result in
increased fuel economy, and may be used as indicated.
Higher upshift speeds may be used to obtain a desired
acceleration rate.
6 Speed Manual Transmission Shift Speed in mph (km/h)
Engine Model Axle Accel-
eration Rate 1
to 2 2
to 3 3
to 4 4
to 5 5
to 6
3.7L 1500 ALL ACCEL
&
CRUISE 15
(24) 10
(16) 24
(39) 19
(31) 34
(55) 27
(44) 47
(76) 37
(60) 56
(90) 41
(66)
4.7L 1500 ALL ACCEL
&
CRUISE 15
(24) 25
(40) 40
(65) 45
(72) 50
(81)
Downshifting
Moving from a high gear down to a lower gear is
recommended to preserve brakes when driving down
steep hills. In addition, downshifting at the right time
provides better acceleration when you desire to resume
speed. For acceleration at speeds less than 20 mph (30
km/h), 2nd gear is recommended.
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This Electronically Shifted transfer case provides 5 mode
positions: 2 wheel drive (2WD), 4WD AUTO, 4WD HI,
Neutral and 4WD Lo.
The Electronically Shifted transfer case is designed to be
driven in the 2 wheel drive position (2WD) or 4 wheel
drive position (4WD AUTO) for normal street and high-
way conditions (dry hard surfaced roads). Driving the
vehicle in 2WD will have greater fuel economy benefits,
as the front axle is not engaged in 2WD.
For variable driving conditions the 4WD AUTO mode
can be used. In this mode the front axle is engaged, but
the vehicle’s power is sent to the rear wheels. Four wheel
drive will be automatically engaged when the vehicle
senses a loss of traction. Because the front axle is en-
gaged, this mode will result in lower fuel economy than
the 2WD mode. When additional traction is required, the transfer case
4WD HI and 4WD LO 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 rotating the 4WD Control Switch to the
desired position - see Shifting Procedure section for
specific shifting instructions. The 4WD HI and 4WD LO
positions are designed for loose, slippery road surfaces
only. Driving in the 4WD HI and 4WD LO positions on
dry hard surfaced roads may cause increased tire wear
and damage to the driveline components.
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WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
CAUTION!
Prolong operation of the steering system at the end
of the steering wheel travel will increase the steering
fluid temperature and should be avoided when
possible. Damage to the power steering pump may
occur.
MULTI DISPLACEMENT SYSTEM (MDS) - 5.7L
Engine Only
This feature offers improved fuel economy by shutting
off four of the engine’s eight cylinders during light load
and cruise conditions. The system is automatic with no
driver inputs or additional driving skills required.
NOTE: The MDS system may take some time to return
to full functionality after a battery disconnect.
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2. Economy—
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Underinflation also increases tire
rolling resistance and results in higher fuel consumption.
3. Ride Comfort and Vehicle Stability—
Proper tire inflation contributes to a comfortable ride.
Overinflation produces a jarring and uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed on either
the face of the driver’s door or the driver’s side “B” pillar.
Some vehicles may have Supplemental Tire Pressure
Information for vehicle loads that are less than the
maximum loaded vehicle condition. These pressure con-
ditions will be found in the “Supplemental Tire Pressure
Information” section of this manual. The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to
check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
Tire Placard Location
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CAUTION!
3500 Dual Rear Tires have only one approved direc-
tion of rotation. This is to accommodate the asym-
metrical design (tread pattern) of the ON/OFF road
tire and the use of Outline White Letter (OWL) tires.
•When replacing a flat, the spare tire may have to
be remounted on the rim or installed at a different
location to maintain the correct placement of the
tire on the wheel relative to the tire/wheel posi-
tion on the truck. For example, if the spare is used
to replace an outer rear tire it will have to be
remounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetri-
cal tires and the white writing of the OWL tires
will maintain proper position.
FUEL REQUIREMENTS
All engines (except 5.7L engines) are de-
signed to meet all emissions regulations
and provide excellent fuel economy and
performance when using high quality un-
leaded “regular” gasoline having an oc-
tane rating of 87. The routine use of pre-
mium gasoline is not recommended.
Under normal conditions the use of premium fuel will
not provide a benefit over high quality regular gasolines
and in some circumstances may result in poorer perfor-
mance.
The 5.7L engine is designed to meet all
emissions regulations and provide satisfac-
tory fuel economy and performance when
using high quality unleaded gasoline hav-
ing an octane range of 87 to 89. The manu-
facturer recommends the use of 89 octane
for optimum performance.The routine use
3.7L/4.7L Engines
5.7L Engines
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of premium gasoline is not recommended. The use of
premium gasoline will provide no benefit over high
quality regular and mid-grade gasolines, and in some
circumstances may result in poorer performance.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of “regular” gasoline be-
fore considering service for the vehicle.
Over 40 auto manufacturers world-wide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance and durability for your vehicle. We recommend the use
of gasolines that meet the WWFC specifications if they
are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline.”
Reformulated gasolines contain oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
We strongly support the use of reformulated gasolines.
Properly blended reformulated gasolines will provide
excellent performance and durability for the engine and
fuel system components.
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Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE and ETBE. Oxygen-
ates are required in some areas of the country during the
winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.
CAUTION!
DO NOT use gasolines containing METHANOL.
Gasoline containing methanol may damage critical
fuel system components.
MMT In Gasoline
MMT is a manganese-containing metallic additive that is
blended into some gasoline to increase octane. Gasolines
blended with MMT provide no performance advantage
beyond gasolines of the same octane number without
MMT. Gasolines blended with MMT reduce spark plug
life and reduce emission system performance. We recom-
mend that gasolines free of MMT be used in your vehicle.
The MMT content of gasoline may not be indicated on
the gasoline pump; therefore, you should ask your gaso-
line retailer whether or not his/her gasoline contains
MMT.
It is even more important to look for gasolines without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited in Federal and California reformulated gasolines.
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