transmission CHEVROLET KODIAK 2008 User Guide
[x] Cancel search | Manufacturer: CHEVROLET, Model Year: 2008, Model line: KODIAK, Model: CHEVROLET KODIAK 2008Pages: 384, PDF Size: 5.4 MB
Page 89 of 384

The engine idle speed will return to normal once the
following conditions are met:
•Once engine coolant temperature reaches about
150°F (65°C).
•The intake temperature reaches a certain level.
The high idle speed will be temporarily interrupted and
the engine speed will return to normal if any of the
following conditions occur:
•The brake pedal is applied.
•The accelerator pedal is pressed.
•The automatic transmission is shifted out of
PARK (P) or NEUTRAL (N).
•The clutch pedal on the manual transmission is
pressed.
•Vehicle speed is detected.
Once these conditions no longer exist, the engine idle
speed will slowly increase to high idle after the
normal delay, if the conditions for engine coolant
temperature and air intake temperature are still met.
Engine Checks Before Operating
When you have started your engine, let it run for
20 to 30 seconds before you put a load on the
engine. But do not leave the vehicle while the engine
is running.
Avoid unnecessary idling of diesel engine equipped
vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature causes
several conditions which affect engine operation and
reduce engine life.
The engine should be permitted to go through a
warm-up period. Operate the vehicle at a minimum of
600 rpm during the warm-up period. During this
period and during operation, the following observations
should be made.
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Page 92 of 384

Diesel Engine Exhaust Brake
If your vehicle has a Isuzu 6H Diesel Engine, it may
have an exhaust brake, which is located in the exhaust
system.
If your vehicle has a 6.6L DURAMAX
®6600 or
Caterpillar®Diesel Engine, it may have an exhaust
brake, which is controlled through the turbocharger.
The exhaust brake for both engines operates the same.
The exhaust brake switch
is located in the instrument
panel switchbank.
Push the bottom of the switch to turn the exhaust brake
on. When you push the top of the switch, the exhaust
brake will turn off.
There is an indicator light on the instrument panel
similar to the symbol on the switch, that comes on when
the exhaust brake is active. SeeExhaust Brake
Indicator Light on page 3-40for more information.While using the exhaust brake, the proper gear range
selection is important. The exhaust brake is most
effective if the gear range selected is the lowest possible
range that does not allow the engine rpm to go more
than 200 rpm above rated (full load) rpm. If you have a
Caterpillar
®Diesel Engine, do not exceed 2900 rpm.
If you have an Isuzu 6H Diesel engine, do not exceed
2550 rpm. If your vehicle has a DURAMAX
®6600
Diesel Engine, do not exceed 3600 rpm.
If your vehicle has an Allison
®1000/2200/2300/
2350/2500/2550 series automatic transmission and this
button is pressed, the transmission downshifts to a
factory default setting of third gear. To change
the default setting, or for more information on factory
default settings, contact your dealer/retailer for
assistance.
The accelerator and clutch pedals must be released in
order for the exhaust brake to engage. The exhaust
brake will automatically shut off when the antilock brake
system is active.
If your vehicle has a Caterpillar
®Diesel Engine or a
DURAMAX®6600 Diesel Engine, the exhaust brake will
become active in cruise control when you exceed the
set speed by 3 to 5 mph.
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Page 93 of 384

Two-Speed Rear Axle
The Two-Speed rear axle lets the driver select Low
Range and High Range. Low Range provides good
starting torque and pulling power. When selecting High
Range the axle allows for higher road speed and
fuel economy.
For better performance during off-road or under a heavy
load, shift the axle into Low Range and then operate
the transmission normally.
For better performance on the highway, shift the axle to
High Range and operate the transmission normally.
High or Low Range can be used when additional shifts
between transmission gears is needed while driving
on grades and for better fuel economy.
Notice:Driving in Low Range above 50 mph
(80.5 kph) will damage driveline components. Drive
below 50 mph (80.5 kph) in Low Range.
If your vehicle has this feature, there is a label on the
headliner above the windshield or in another place near
the driver that shows how to use it. Be sure to follow
the directions carefully.
Two-Speed Rear Axle Shift Control
Operation
The rear axle shift control
switch for automatic and
manual transmissions
is located in the instrument
panel switchbank.
Press the bottom of the switch for High Range and the
top of the switch for Low Range. The switch indicator
light comes on when the High Range is selected.
Always start your vehicle in motion with the two-speed
axle in low range.
Shifting on a Downgrade
Do not shift the two-speed axle when driving on a
downgrade. The speed of the vehicle moving downhill
may make it hard to shift the axle into either Low or
High Range.
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Page 94 of 384

Shifting
Upshifting the Axle
To shift from Low to High Range:
1. Press the bottom of the switch to shift the axle
control from Low to High.
2. Release the accelerator pedal until the shift applies.
3. Then push the accelerator pedal.
Axle upshift can be abrupt, causing the vehicle to jerk.
Release the accelerator slowly for a smooth shift.
For manual transmissions, use the clutch while pressing
the accelerator for a smooth shift.
Downshifting the Axle
To shift from High to Low Range:
1. Press the top of the switch to shift from High to
Low Range.
2. Release the accelerator pedal.
3. Then push the accelerator pedal slowly until the
axle shifts.
Split Upshift
(Manual Transmissions Only)
To downshift the axle with a transmission upshift:
1. Push the clutch.
2. Shift the Transmission to a higher gear.
3. Shift the axle control from High to Low Range.
4. Release the clutch.
5. Push the accelerator pedal until the axle shifts.
Split Downshift
(Manual Transmission Only)
To upshift the axle with a transmission downshift:
1. Shift the axle control from Low to High Range.
2. Push the clutch.
3. Shift the transmission to a lower gear.
4. Release the clutch.
5. Push the accelerator pedal until the axle shifts.
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Page 95 of 384

Automatic Transmission Operation
Your vehicle has either an Allison®five-speed or
six-speed automatic transmission. This part of the
manual covers the basics of these. With these
transmissions, you will find another Allison
®manual in
your vehicle that goes into more detail. On the headliner,
in front of and above the driver, or in some other
place near the driver, you will see a label that describes
important operating facts about the automatic
transmission in your vehicle. Make sure you follow the
instructions on this label.
Be sure to keep your parking brake set until you are
ready to shift into DRIVE (D). SeeParking Brake (With
Hydraulic Brakes) on page 2-38orParking Brake
(With Air Brakes) on page 2-41for parking brake
procedure. Press the brake pedal while shifting from
NEUTRAL (N) or PARK (P) to a drive gear.
All vehicles that have an with automatic transmission
can be started in PARK (P), if equipped, or in
NEUTRAL (N). See the Allison
®Transmission
Operator’s Manual in your vehicle for more information
about this.
{CAUTION:
It can be dangerous to get out of your vehicle
without the parking brake rmly set. Your
vehicle can roll. If you have left the engine
running, the vehicle can move suddenly. You or
others could be injured. To be sure your vehicle
will not move, even when you are on fairly level
ground, always set the parking brake.
{CAUTION:
Shifting into a drive gear while the engine is
running at high speed is dangerous. Unless
your foot is rmly on the brake pedal, your
vehicle could move very rapidly. You could
lose control and hit people or objects. Do not
shift into a drive gear while your engine is
running at high speed.
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Page 96 of 384

Overdrive Defeat
If your vehicle has this feature, you can select not to
shift up to fifth gear. This is useful when towing or under
a heavy load.
The overdrive defeat
switch is located in the
instrument panel to
the right of the steering
column.
Press the switch to limit the transmission to fourth gear.
This will allow for fewer downshifts while pulling a
trailer or under a heavy load. The indicator light in the
switch comes on whenever overdrive defeat is active.
Manual Transmission Operation
Using the Clutch
When you are starting to move the vehicle, it is important
to begin with the engine speed at idle. Then start to
engage the clutch and listen for an engine speed drop of
about 100 rpm. At this point, the clutch is engaging, so
you should increase the engine speed and fully engagethe clutch. It is important not to increase the engine speed
sooner or before the clutch begins its engagement. If you
do, you can cause damage to your vehicle.
Double-Clutching
You must use the double-clutching method when you
shift an unsynchronized gear set. Disengage the clutch,
shift to NEUTRAL and engage the clutch. When
upshifting, slow the engine until the engine rpm and
road speed match. When downshifting, accelerate the
engine until the engine rpm and road speed match. Then
quickly disengage the clutch and move the shift lever
to the next gear position and engage the clutch.
Eaton®Fuller®Five and Six-Speed
Transmissions and TTC Spicer
Seven-Speed Transmissions
These transmissions have gears that automatically
synchronize when you shift up or down (except
FIRST (1) gear on the five-speed and seven-speed
transmission which is unsynchronized). Choose the gear
that will maintain the road speed you want while
keeping the engine above two-thirds of the governed
speed. When the engine speed drops below two-thirds
of the governed speed, shift into the next lower gear
before your engine begins to lug. When you shift down,
be sure to double-clutch if required.
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Page 97 of 384

Eaton®Fuller®Nine and Ten-Speed
Non-Synchronized Manual
Transmissions
If your vehicle has one of these transmissions the
engine rpm and road speed must match when upshifting
and downshifting. The label above the windshield will
tell you the operating basics you need to know.
The following are driving tips.
•Always choose an initial starting gear suitable for
the load and terrain.
•Always use double-clutching procedures when
shifting.
•Never move the range shift lever to the LO speed
gear position after HI range preselection, or
anytime the transmission is in the HI range.
•Never move the range knob or lever with the shift
lever in NEUTRAL while the vehicle is moving.
•Never make a range shift while moving in
REVERSE (R).
Clutch Brake (Vehicles with
Non-Synchronized Transmission)
A clutch brake is used to stop transmission input shaft
rotation so that FIRST (1) or REVERSE (R) gear
selection can be initiated when the vehicle is at a
standstill and the engine is idling.
Press the clutch pedal all the way down to the floorboard
to apply the clutch brake.
When using the clutch brake, disengage the clutch
pedal and shift the transmission into either the initial
starting gear or REVERSE (R). If the tooth-butting
occurs between the clutching teeth, re-engage the clutch
while applying light pressure to the shift lever. This
will provide for a smooth shift into either FIRST (1) or
REVERSE (R) gear.
Notice:Using the clutch brake for shifting into any
gear other than FIRST (1) or REVERSE (R) may
cause premature wear of the clutch brake and make
gear shift effort more difficult. Do not use the
clutch brake for shifting after engaging FIRST (1) or
REVERSE (R).
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Page 98 of 384

Power Take-Off (PTO)
Your vehicle may have
power take-off (PTO). The
PTO switch is located
on the instrument panel.
An indicator in the switch comes on to show PTO is
active. SeeHigh Idle System on page 2-20for
more information.
A PTO is a gearbox or mechanical device used to
transmit mechanical power from the powertrain, through
gears or a transmission, to another mechanical or
hydraulic device. Before using a PTO, refer to the
manufacturer’s or installer’s instructions.
Four-Wheel Drive
If your vehicle has four-wheel drive, you can send the
engine’s driving power to all four wheels for extra
traction. To get the most satisfaction out of four-wheel
drive, you must be familiar with its operation. Read
the part that follows before using four-wheel drive. You
should use two-wheel drive high for most normal
driving conditions.
Notice:Driving on clean, dry pavement in
four-wheel drive for an extended period of time can
cause premature wear on your vehicle’s powertrain.
Do not drive on clean, dry pavement in Four-Wheel
Drive for extended periods of time.
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Page 100 of 384

Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2m4m4nN
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeTowing Your Vehicle on page 4-24for further
information.
2
m(Two-Wheel High):This setting is for driving in
most street and highway situations. The transfer
case does not drive the front axle in two-wheel drive.
The front-axle spins if the front wheel hubs are locked.
Be sure to unlock the hubs to achieve the best fuel
economy.4
m(Four-Wheel High):Use Four-Wheel High when
you need extra traction, such as on snowy or icy
roads or in most off-road situations. Be sure the front
wheel hubs are locked when you want to drive in
Four-Wheel High.
4
n(Four-Wheel Low):This setting sends maximum
power to all four wheels. You might choose Four-Wheel
Low if you are driving off-road in deep sand, deep
mud, and climbing or descending steep hills. Be sure
the front wheel hubs are locked when you want to drive
in Four-Wheel Low.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be injured. If you are going to leave
your vehicle, set the parking brake and shift
the transmission to PARK (P) and make sure
the transfer case is in a drive gear.
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Page 101 of 384

Notice:If your vehicle has an Allison®transmission
and you try to put the transmission in PARK (P)
while the transfer case is in Four-Wheel Low,
the transmission might not go into PARK (P) and
could damage your vehicle. When parking your
vehicle, make sure the transfer case is in Two-Wheel
High or Four-Wheel High.
NEUTRAL:Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle.
Shifting Into Four-Wheel High
Turn the knob to four-wheel high. This can be done at
3 mph or less, while you are shifting out of Four-Wheel
Low. The indicator light flashes while shifting. It
remains on after the shift is complete. Be sure to lock
your front hubs.
Shifting Into Two-Wheel High
Turn the knob to Two-Wheel High. This can be done
at 3 mph or less, while you are shifting out of
Four-Wheel Low.
Shifting Into Four-Wheel Low
To shift to Four-Wheel Low, the vehicle’s engine must
be running and the vehicle must be stopped or
moving less than 3 mph (5 km/h) with the transmission
in NEUTRAL (N). The preferred method for shifting
into Four-Wheel Low is to have your vehicle moving
1 or 2 mph (1.6 to 3.2 km/h). Turn the knob to
Four-Wheel Low. You must wait for the Four-Wheel Low
indicator light to stop flashing and remain on before
shifting the transmission into gear. Be sure to lock the
front hubs.
Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for the
Four-Wheel Drive Low indicator light to stop ashing
before shifting the transmission into gear.
If you turn the knob to Four-Wheel Low while your
vehicle is in gear and/or moving, the Four-Wheel Low
indicator light flashes for 30 seconds and does not
complete the shift unless your vehicle is moving less
than 3 mph (4.8 km/h) and the transmission is in
NEUTRAL (N). After 30 seconds, the transfer case
returns to the setting last chosen. If your vehicle is in
gear and moving less than 3 mph (4.8 km/h), the
transfer case shifts to Four-Wheel High.
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