2003 GMC SONOMA Owner's Manual

Automatic Transmission Operation
Your automatic transmission has a shift lever on the
steering column.
There are several different positions for your shift lever.
It features an electronic shift position indicator within
the instrument cluster. This display must be powered
anytime the shift lever is capable of being moved out of
PARK (P). This means that if your key is in OFF, but
not locked, there will be a small current drain on
your battery which could discharge your battery over a
period of time. If you need to leave your key in the
ignition in OFF for an extended period, it is
recommended that you disconnect the battery cable
from the battery to prevent discharging your battery.PARK (P):This position locks your rear wheels. It’s the
best position to use when you start your engine because
your vehicle can’t move easily.
{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brakefirmly set. Your vehicle can roll.
Don’t 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 won’t move, even when you’re on fairly
level ground, always set your parking brake and
move the shift lever to PARK (P). See“Shifting
Into Park (P)”in the Index. If you’re pulling a
trailer, see“Towing a Trailer”in the Index.
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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 2-35.
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage your transmission.
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 4-40.
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
“racing”(running at high speed) is dangerous.
Unless your foot isfirmly on the brake pedal,
your vehicle could move very rapidly. You
could lose control and hit people or objects.
Don’t shift into a drive gear while your engine
is racing.
Notice:Damage to your transmission caused by
shifting out of PARK (P) or NEUTRAL (N) with
the engine racing isn’t covered by your warranty.
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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.
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:If your wheels won’t turn, don’t try to drive.
This might happen if you were stuck in very deep
sand or mud or were up against a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don’t hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into PARK (P) to hold your vehicle in
position on a hill.
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Manual Transmission Operation
Five-Speed
This is your shift pattern.
Here’s how to operate your transmission:
FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal as
you slowly press down on the accelerator pedal.
You can shift into FIRST (1) when you’re going less
than 20 mph (30 km/h). If you’ve come to a complete
stop and it’s hard to shift into FIRST (1), put the
shift lever in NEUTRAL and let up on the clutch.
Press the clutch pedal back down. Then shift into
FIRST (1).SECOND (2):Press the clutch pedal as you let up on
the accelerator pedal and shift into SECOND (2).
Then, slowly let up on the clutch pedal as you press the
accelerator pedal.
THIRD, FOURTH AND FIFTH (3, 4 and 5):Shift into
THIRD (3), FOURTH (4) and FIFTH (5) the same
way you do for SECOND (2). Slowly let up on the clutch
pedal as you press the accelerator pedal.
To stop, let up on the accelerator pedal and press the
brake pedal. Just before the vehicle stops, press
the clutch pedal and the brake pedal, and shift to
NEUTRAL.
NEUTRAL:Use this position when you start or idle
your engine.
REVERSE (R):To back up, press the clutch pedal.
After the vehicle stops, shift into REVERSE (R).
For vehicles equipped with the
VORTEC™4300 V6 engine, you must wait six seconds
before shifting into REVERSE (R). Slowly let up on
the clutch pedal as you press the accelerator pedal.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage your transmission.
Shift to REVERSE (R) only after your vehicle is
stopped.
Use REVERSE (R), along with the parking brake, for
parking your vehicle.
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Up-Shift Light
If you have a manual
transmission, you have a
SHIFT light.
This light will show you when to shift to the next higher
gear for best fuel economy.
When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions let you.
For the best fuel economy, accelerate slowly and shift
when the light comes on.
While you accelerate, it is normal for the light to go on
and off if you quickly change the position of the
accelerator. Ignore the SHIFT light when you downshift.
If your vehicle has four-wheel-drive and is equipped
with a manual transmission, disregard the SHIFT light
when the transfer case is in 4LO.
Shift Speeds
{CAUTION:
If you skip a gear when you downshift, you
could lose control of your vehicle. You could
injure yourself or others. Don’t shift down
more than one gear at a time when you
downshift.
Four-Wheel Drive
If 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.
SeeOff-Road Recovery on page 4-10.
You should use two-wheel high (2HI) for most normal
driving conditions.
Notice:Driving in the 4-WHEEL HIGH (4HI) or
4-WHEEL LOW (4LO) positions for a long time on
dry or wet pavement could shorten the life of
your vehicle’s drivetrain.
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Electronic Transfer Case
If your four-wheel-drive
vehicle has the electronic
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: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: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: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 willflash 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.
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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) in vehicles equipped
with an automatic transmission or the clutch pedal
engaged in vehicles equipped with a manual
transmission. 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 stopflashing
and remain illuminated before shifting your transmission
into gear or releasing the clutch pedal.
If the 4LO button is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light willflash 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.
On automatic transmission equipped vehicles, 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 isflashing, 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) or the clutch pedal
engaged. 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 stopflashing
and remain illuminated before shifting your transmission
into gear or releasing the clutch pedal.
If the 4HI button is pressed when your vehicle is in gear
and/or moving, the 4HI indicator light willflash 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.
On automatic transmission equipped vehicles, 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 isflashing, 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.
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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
cause your rear brakes to overheat. You may have
to replace them, and you could also damage
other parts of your vehicle.
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 4-51. That section
shows what to dofirst to keep the trailer from moving.
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