GMC SONOMA 2003 Owner's Manual

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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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 brakefirmly 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 won’t
move, even when you’re on fairly level ground,
use the steps that follow. If you’re pulling a
trailer, see“Towing a Trailer”in the Index.
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.
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•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 brakefirmly set.
And, if you leave the vehicle with the engine
running, it could overheat and even catchfire.
You or others could be injured. Don’t 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 isfirmly 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) withoutfirst
pulling it toward you. If you can, it means that the
shift lever wasn’t fully locked into PARK (P).
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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 mayfind 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.
Tofind out how, seeShifting Into Park (P) on page 2-33.
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. 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 2-25.
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 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 vehiclefixed as soon as possible.
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Parking Your Vehicle
If you have a manual transmission, before you get out
of your vehicle, move the shift lever into REVERSE (R),
andfirmly apply the parking brake. Once the shift
lever has been placed into REVERSE (R) with the clutch
pedal pressed in, you can turn the ignition key to
OFF, remove the key and release the clutch.
If you are parking on a hill, or if your vehicle is pulling a
trailer, seeTowing a Trailer on page 4-51.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Don’t park
over papers, leaves, dry grass or other things
that can burn.
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Engine Exhaust
{CAUTION:
Engine exhaust can kill. It contains the gas
carbon monoxide (CO), which you can’t see or
smell. It can cause unconsciousness and death.
You might have exhaust coming in if:
•Your exhaust system sounds strange or
different.
•Your vehicle gets rusty underneath.
•Your vehicle was damaged in a collision.
CAUTION: (Continued)
CAUTION: (Continued)
•
Your vehicle was damaged when driving
over high points on the road or over road
debris.
•Repairs weren’t done correctly.
•Your vehicle or exhaust system had been
modified improperly.
If you ever suspect exhaust is coming into your
vehicle:
•Drive it only with all the windows down to
blow out any CO; and
•Have your vehiclefixed immediately.
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Running Your Engine While You
Are Parked
It’s better not to park with the engine running. But if you
ever have to, here are some things to know.
{CAUTION:
Idling the engine with the climate control
system off could allow dangerous exhaust into
your vehicle. See the earlier Caution under
“Engine Exhaust.”
Also, idling in a closed-in place can let deadly
carbon monoxide (CO) into your vehicle even if
the fan is at the highest setting. One place this
can happen is a garage. Exhaust—with
CO—can come in easily. NEVER park in a
garage with the engine running.
Another closed-in place can be a blizzard.
See“Winter Driving”in the Index.
{CAUTION:
It can be 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’ve 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).
Follow the proper steps to be sure your vehicle won’t
move. SeeShifting Into Park (P) on page 2-33.
If you’re pulling a trailer, seeTowing a Trailer on
page 4-51.
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