GMC SIERRA 2005 Owner's Manual

Passlock®
Your vehicle is equipped with the
Passlock®theft-deterrent system.
Passlock
®is a passive theft-deterrent system.
Passlock®enables fuel if the ignition lock cylinder is
turned with a valid key. If a correct key is not used or the
ignition lock cylinder is tampered with, fuel is disabled.
If the engine stalls and the security light ashes,
wait until the light stops ashing before trying to restart
the engine. Remember to release the key from
START as soon as the engine starts.
If the engine is running and the security light comes on,
you will be able to restart the engine if you turn the
engine off. However, your Passlock
®system is
not working properly and must be serviced by your
dealer. Your vehicle is not protected by Passlock
®at this
time. You may also want to check the fuse. See
Fuses and Circuit Breakers on page 5-122. See your
dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-5.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
break-in. But it will perform better in the long run if
you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the rst 500 miles (805 km).
Do not drive at any one speed — fast or
slow — for the rst 500 miles (805 km). Do not
make full-throttle starts.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time your new
brake linings are not yet broken in. Hard stops
with new linings can mean premature wear
and earlier replacement. Follow this breaking-in
guideline every time you get new brake
linings.
Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-68for more information.
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Ignition Positions
With the key in the ignition switch, you can turn it to
four different positions.
Notice:If your key seems stuck in LOCK and you
cannot turn it, be sure you are using the correct key;
if so, is it all the way in? Turn the key only with your
hand. Using a tool to force it could break the key or
the ignition switch. If none of these works, then your
vehicle needs service.A (Lock):This position locks your ignition when the key
is removed. The steering locks when equipped with a
manual transmission. It is a theft-deterrent feature. You
will only be able to remove your key when the ignition is
turned to LOCK.
B (Accessory):This position allows you to use things
like the radio, power windows and the windshield
wipers when the engine is off.
{CAUTION:
On manual transmission vehicles, turning the
key to LOCK will lock the steering column and
result in a loss of ability to steer the vehicle.
This could cause a collision. If you need to
turn the engine off while the vehicle is moving,
turn the key only to ACCESSORY. Do not
press the key release button while the vehicle
is moving.
C (Run):This is the position for driving.
D (Start):This position starts your engine.
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Key Release Button
(Manual Transmission)
The ignition key cannot be
removed from the ignition
of manual transmission
vehicles unless the key
release button is used.
To remove the key on manual transmission vehicles, turn
the key to ACCESSORY, then press the button and turn
the key to LOCK. Do not hold the button in while turning
the key to ACCESSORY. Pull the key straight out.
Retained Accessory Power (RAP)
If the vehicle has Retained Accessory Power (RAP),
certain features will continue to operate for up to
10 minutes after the ignition key is turned to LOCK
unless a door is opened.
Starting Your Engine
Your vehicle is equipped with Starter Motor Control.
This feature assists in starting the engine and protects
the electrical system. This feature may cause the
engine to crank even after the ignition key is not in
START.
Automatic Transmission
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine will not start in any other position — that is
a safety feature. To restart when you are already
moving, use NEUTRAL (N) only. If you have a diesel
engine refer to the diesel supplement for the starting
procedure.
Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could damage the
transmission. Shift to PARK (P) only when your
vehicle is stopped.
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Manual Transmission
The gear selector should be in neutral and the parking
brake engaged. Hold the clutch pedal to the oor
and start the engine. Your vehicle will not start if the
clutch pedal is not all the way down — that is a safety
feature.
Starting Your V8 Engine
1. With your foot off the accelerator pedal, turn the
ignition key to START. When the engine starts,
let go of the key. The idle speed will go down as
your engine gets warm.
Notice:Holding your key in START for longer than
15 seconds at a time will disengage the starter
motor, cause your battery to be drained much
sooner, and add excessive heat that can damage
your starter motor. Try not to hold the key in START
for longer than 15 seconds and wait about
15 seconds between each try to help avoid draining
your battery or damaging your starter.
2. If it does not start within 10 seconds, push the
accelerator pedal all the way to the oor, while
you hold the ignition key in START. When
the engine starts, let go of the key and let up on the
accelerator pedal. Wait about 15 seconds between
each try.When starting your engine in very cold weather
(below 0°F or−18°C), do this:
1. With your foot off the accelerator pedal, turn the
ignition key to START and hold it there up to
15 seconds. When the engine starts, let go of
the key.
2. If your engine still will not start, or starts but then
stops, it could be ooded with too much gasoline.
Try pushing your accelerator pedal all the way to the
oor and holding it there as you hold the key in
START for about three seconds. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briey but then stops again, do the
same thing, but this time keep the pedal down
for ve or six seconds. This clears the extra
gasoline from the engine.
Notice:Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you do not, your engine
might not perform properly.
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Engine Coolant Heater
In very cold weather, 0°F (−18°C) or colder, the engine
coolant heater can help. You will get easier starting
and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle. At
temperatures above 32°F (0°C), use of the coolant
heater is not required. Your vehicle may also have an
internal thermostat in the plug end of the cord. This will
prevent operation of the engine coolant heater when
the temperature is at or above 0°F (−18 C°) as noted on
the cord.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The
cord is located on the driver’s side of the engine
compartment, near the power steering uid
reservoir. If you have a diesel engine, refer to
diesel supplement for location.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could be
damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer in the area where you will be parking
your vehicle. The dealer can give you the best advice
for that particular area.
2-25

Automatic Transmission Operation
If your vehicle is equipped with an automatic
transmission, it features an electronic shift position
indicator within the instrument panel cluster. This display
must be powered anytime the shift lever is capable of
being moved out of PARK (P). SeeFuses and
Circuit Breakers on page 5-122.
There are several different positions for your shift lever.
PARK (P):This position locks your rear wheels. It is
the best position to use when you start your engine
because your vehicle cannot move easily. If your vehicle
is equipped with the Allison Transmission
®, use
PARK (P) for stationary operation of the Power Takeoff
(PTO), if equipped. The Allison Transmission
®is
equipped with park pawl designed to hold the higher
weight of commercial medium duty trucks. Therefore, the
Allison Transmission
®uses larger parts than other
automatic transmission. These larger parts may
sometimes make a clunk noise when the selector lever
is moved from DRIVE (D) or REVERSE (R) to
PARK (P). This is normal and there is no damage
occurring during these shifts.
{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brake rmly set. Your vehicle can roll.
Do not leave your vehicle when the engine is
running unless you have to. 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 your
parking brake and move the shift lever to
PARK (P). SeeShifting Into Park (P) (Automatic
Transmission) on page 2-49. If you are pulling
a trailer, seeTowing a Trailer on page 4-68.
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{CAUTION:
If you have four-wheel drive, your vehicle will
be free to roll — even if your shift lever is in
PARK (P) — if your transfer case is in
NEUTRAL. So, be sure the transfer case is in a
drive gear, two-wheel high (2H) or four-wheel
high (4H) or four-wheel low (4L) — not in
NEUTRAL. SeeShifting Into Park (P)
(Automatic Transmission) on page 2-49.
REVERSE (R):Use this gear to back up. If your vehicle
is equipped with the Allison Transmission
®, the R
may blink on the PRNDL if the shift inhibitor is active.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage the transmission.
The repairs would not be covered by your warranty.
Shift to REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission,
seeIf You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-48.NEUTRAL (N):In this position, your engine does not
connect with the wheels. To restart when you are
already moving, use NEUTRAL (N) only. Also, use
NEUTRAL (N) when your vehicle is being towed.
{CAUTION:
Shifting into a drive gear while your 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.
Notice:Shifting out of PARK (P) or NEUTRAL (N)
with the engine running at high speed may damage
the transmission. The repairs would not be
covered by your warranty. Be sure the engine is not
running at high speed when shifting your vehicle.
2-27

DRIVE (D):This position is for normal driving. If you
need more power for passing, and you are:
Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You will shift down to the next gear and have more
power.
DRIVE (D) can be used when towing a trailer, carrying a
heavy load, driving on steep hills or for off-road
driving. You may want to shift the transmission to
THIRD (3) or, if necessary, a lower gear selection if the
transmission shifts too often.
If your vehicle is equipped with the Allison
Transmission
®, it will initially attain rst range when
DRIVE (D) is selected. As vehicle speed increases, the
transmission will upshift automatically through each
available range up to FIFTH (5). As the vehicle slows,
the transmission will downshift automatically.
The Allison Transmission
®uses a shift stabilization
feature to adjust the transmission shift schedule to the
current driving situation to reduce rapid upshifts and
downshifts. This shift stabilization feature is designed to
determine before making an upshift if the engine will
be able to maintain vehicle speed by analyzing
things such as throttle position, vehicle load, and hill
grade. If the shift stabilization feature determinesthat current vehicle speed cannot be maintained, the
transmission does not upshift and instead holds
the current gear. In some cases, this may appear to be
a hanging shift, however the transmission is operating
normally.
The Allison Transmission
®also uses adaptive shift
controls. Adaptive shift controls continually compares
key shift parameters to pre-programmed ideal shift
conditions. The Allison Transmission
®constantly makes
adjustments to improve vehicle performance according
to the way the vehicle is being used, such as with a
heavy load. During this adaptive shift controls process,
some shifts may feel different as the transmission
determines optimum settings for a particular shift.
By using shift stabilization and adaptive shift controls,
the Allison Transmission
®shift schedule is variable and
adjusts to how the vehicle is being used, providing
improved vehicle performance.
THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
SECOND (2):This position gives you more power but
lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want to
use your brakes off and on.
2-28

If you manually select SECOND (2) in a light duty
automatic transmission, the transmission will drive in
second gear. You may use this feature for reducing the
speed of the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces.
FIRST (1):This position gives you even more power
(but lower fuel economy) than SECOND (2). You
can use it on very steep hills, or in deep snow or mud.
If the selector lever is put in FIRST (1) while the
vehicle is moving forward, the transmission will not shift
into rst gear until the vehicle is going slowly enough.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
On cold days, approximately 32°F (0°C) or colder, your
transmission is designed to shift differently. The
transmission uses a warm-up mode shift schedule until
the engine reaches normal operating temperature.
While the transmission is in warm-up mode it is normal
for transmission upshifts to be delayed or held longer.
This feature improves heater performance by giving
quicker vehicle warm-ups.Tow/Haul Mode
If your vehicle has an automatic transmission, it may be
equipped with a Tow/Haul mode. The selector button
is located on the end of the column shift lever. You can
use this feature to assist when towing or hauling a
heavy load. Turn Tow/Haul on and off by pressing the
button until the Tow/Haul indicator light illuminates
on the instrument panel.
2-29

Tow/Haul is a feature on automatic transmission
equipped vehicles that assists when pulling a heavy
trailer or large or heavy load. Tow/Haul mode adjusts the
transmission’s shift pattern to reduce shift cycling,
providing increased performance, vehicle control, and
transmission cooling when towing or hauling heavy loads.
If your vehicle is equipped with an Allison
®transmission,
you may have both Tow/Haul mode and overdrive
disable. See “Tow/Haul Mode” underTowing a Trailer
on page 4-68for more information.
Grade Braking
(Allison Transmission®Only)
Grade braking uses the engine and transmission to slow
a loaded vehicle on hills in addition to using the
brakes, saving on brake wear and increasing vehicle
stability. The Allison Transmission
®, when sensing
the driver’s desire to slow down while driving downhill,
will automatically shift to the next lower gear range
to assist in slowing down the vehicle. Grade braking is
active and automatic both in Tow/Haul mode and
normal shift mode. Grade braking is more aggressive
when in Tow/Haul mode and can automatically downshift
to SECOND (2), which is different than grade braking
while in normal shift mode where automatic downshifts
are limited to FOURTH (4).The tachometer for both the diesel and gasoline engine
shows a dashed red zone and a solid red zone. The
dashed red zone indicates where a transmission
shift occurs for full engine power. When using grade
braking, the transmission’s shift point is adjusted to just
prior to the solid red zone, providing the benet of
additional engine braking.
Grade braking driving within the dashed red zone is
normal, both the diesel and gasoline engine have been
designed for this grade braking feature. Do not allow
the engine to go into the solid red zone. Apply the
vehicle’s brakes for a short time to slow down if you are
driving on a long hill and the tachometer needle
enters the solid red zone. SeeTowing a Trailer on
page 4-68for more information.
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