2004 GMC SONOMA Owner's Manual

Make sure the shift lever is fully in PARK (P) before
starting the engine. Your vehicle has an automatic
transmission shift lock control system. You have to fully
apply your regular brakes before you can shift from
PARK (P) when the ignition key is in RUN. If you cannot
shift out of PARK (P), ease pressure on the shift
lever–push the shift lever all the way into PARK (P) as
you maintain brake application. Then move the shift
lever into the gear you wish. SeeShifting Out of Park (P)
on page 2-28.
REVERSE (R):Use this gear to back up.
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,
see If You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-42.
NEUTRAL (N):In this position, your engine doesn’t
connect with the wheels. To restart when you’re already
moving, use NEUTRAL (N) only.
{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 racing may damage the
transmission. The repairs would not be covered by
your warranty. Be sure the engine is not racing
when shifting your vehicle.
DRIVE (D):This position is for normal driving. If you
need more power for passing, and you’re:
•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’ll shift down to the next gear and have more power.
2-21

DRIVE (D) should not be used when towing a trailer,
carrying a heavy load, driving on steep hills, or for
off-road driving. Select THIRD (3) when operating the
vehicle under any of these conditions.
THIRD (3):This position is also used for normal driving,
however, it offers more power and lower fuel economy
than DRIVE (D). You should use THIRD (3) when towing
a trailer, carrying a heavy load, driving on steep hills
or winding roads or for off-road driving.
SECOND (2):This position gives you more power but
lower fuel economy than THIRD (3). 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. You can
also use SECOND (2) for starting 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
shift lever is put in FIRST (1) while the vehicle is moving
forward, the transmission won’t shift into FIRST (1)
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.Four-Wheel Drive
Your vehicle has four-wheel drive. You can send your
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. See
Off-Road Recovery on page 4-11.
You should use two-wheel high (2HI) for most normal
driving conditions.
Notice:Driving on pavement in four-wheel drive for
an extended period of time may cause premature
wear on your vehicle’s powertrain. Do not drive
in four-wheel drive on pavement for extended
periods of time.
2-22

Transfer Case
The transfer case buttons
are to the right of the
steering wheel on
the instrument panel.
Use these buttons to shift into and out of
four-wheel-drive. You can choose among three driving
settings:
2HI (Two-Wheel Drive High):This setting is for driving
in most street and highway situations. Your front axle
is not engaged in two-wheel drive. When this light
is turned on, it is about one-half as bright as the others.4HI (Four-Wheel Drive High):This setting engages
your front axle to help drive your vehicle. Use 4HI when
you need extra traction, such as on snowy or icy
roads, or in most off-road situations.
4LO (Four-Wheel Drive Low):You may never need
4LO. This setting also engages your front axle to
give you extra traction. It sends the maximum power to
all four wheels. You might choose 4LO if you were
driving off-road in sand, mud or deep snow and climbing
or descending steep hills.
Indicator lights in the buttons show you which setting
you are in. The indicator lights will come on briefly when
you turn on the ignition and one will stay on. If the
lights do not come on, you should take your vehicle in
for service. An indicator light will flash while shifting.
It will remain illuminated when the shift is completed.
Shifting from 2HI to 4HI
Press and release the 4HI button. This can be done at
any speed, and the front axle will lock automatically.
Shifting from 4HI to 2HI
Press and release the 2HI button. This can be done at
any speed, and the front axle will unlock automatically.
2-23

Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4LO, the vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N). The preferred method
for shifting into 4LO is to have your vehicle moving 1 to
2 mph (1.6 to 3.2 km/h). Press and release the 4LO
button. You must wait for the 4LO indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.
If the 4LO button is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light will flash for
30 seconds and not complete the shift unless your
vehicle is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N) or the clutch pedal
engaged.
If your transfer case does not shift into 4LO, your
transmission indicator switch may require adjustment.
With your transmission in NEUTRAL (N), press and
release the 4LO button. While the 4LO indicator light is
flashing, shift your transmission into PARK (P). Wait
until the 4LO indicator light remains illuminated before
shifting your transmission into gear. This will get
you into 4LO, but you should take your vehicle in for
service to restore normal operation.
Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2HI, your vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N). The preferred method
for shifting out of 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the 4HI
button. You must wait for the 4HI indicator light to
stop flashing and remain illuminated before shifting your
transmission into gear.
If the 4HI button is pressed when your vehicle is in gear
and/or moving, the 4HI indicator light will flash for
30 seconds but not complete the shift unless the vehicle
is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N) or the clutch pedal
engaged.
If your transfer case does not shift into 4HI, your
transmission indicator switch may require adjustment.
With your transmission in NEUTRAL (N), press and
release the 4HI button. While the 4HI indicator light is
flashing, shift your transmission into PARK (P). Wait until
the 4HI indicator light remains illuminated before
shifting your transmission into gear. This will get you
into 4HI, but you should take your vehicle in for service
to restore normal operation.
2-24

Parking Brake
The parking brake is located near the bottom of the
instrument panel on the driver’s side of the vehicle.
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot. If the ignition is on, the
brake system warning light will come on.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Verify that
the parking brake is fully released and the brake
warning light is off before driving.
To release the parking brake, hold the regular brake
pedal down. Pull the BRAKE RELEASE lever fully. It is
located on the bottom off the instrument panel on
the driver’s side of the vehicle.If you are towing a trailer and you must park on a hill,
seeTowing a Trailer on page 4-55. That section
shows what to do first to keep the trailer from moving.
2-25

Shifting Into Park (P)
{CAUTION:
It can be 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. 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, use the steps that follow. If you are
pulling a trailer, seeTowing a Trailer on
page 4-55.
1. Hold the brake pedal down with your right foot and
set the parking brake.2. Move the shift lever into PARK (P) position like this:
•Pull the lever toward you.
2-26

•Move the lever up as far as it will go.
3. Turn the ignition key to LOCK.
4. Remove the key and take it with you. If you can
leave your vehicle with the key, your vehicle is in
PARK (P).
Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in
PARK (P) with the parking brake rmly set.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re.
You or others could be injured. Do not leave
your vehicle with the engine running.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and your
parking brake is firmly set before you leave it. After
you’ve moved the shift lever into PARK (P), hold
the regular brake pedal down. Then, see if you can
move the shift lever away from PARK (P) without first
pulling it toward you. If you can, it means that the
shift lever wasn’t fully locked into PARK (P).
2-27

Torque Lock
If you are parking on a hill and you don’t shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may find it difficult to pull the
shift lever out of PARK (P). This is called “torque
lock” To prevent torque lock, set the parking brake and
then shift into PARK (P) properly before you leave
the driver’s seat. To find out how, seeShifting Into
Park (P) on page 2-26.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission, so
you can pull the shift lever out of PARK (P).
Shifting Out of Park (P)
Your vehicle has an automatic transmission shift lock
control system which locks the shift lever in PARK when
the ignition is in the OFF position. In addition, you
have to fully apply the regular brakes before you can
shift from PARK (P) when the ignition is in RUN.
SeeAutomatic Transmission Operation on page 2-20.
If you cannot shift out of PARK (P), ease pressure
on the shift lever. Push the shift lever all the way into
PARK (P) as you maintain brake application and
then move the shift lever into the gear you want. You
must press the shift lever button on the shift lever.
If you ever hold the brake pedal down but still can’t shift
out of PARK (P), try this:
1. Turn the key to OFF.
2. Apply and hold the brake until the end of Step 4.
3. Shift the transmission to NEUTRAL (N).
4. Start the vehicle and then shift to the drive gear
you want.
5. Have the vehicle fixed as soon as you can.
2-28