2003 GMC SONOMA clutch

Retained Accessory Power (RAP)
Your vehicle is equipped with a Retained Accessory
Power (RAP) feature which will allow certain features of
your vehicle to continue to work for up to 20 minutes
after the ignition key is turned to OFF.
Your radio, power windows, sunroof and overhead
console will work when the ignition key is in RUN or
ACCESSORY. Once the key is turned from RUN
to OFF, these features will continue to work for up to
20 minutes or until a door is opened.
Starting Your Engine
Automatic Transmission
Move your shift lever to PARK (P) or NEUTRAL (N). Your
engine won’t start in any other position–that’s a safety
feature. To restart when you’re already moving, use
NEUTRAL (N) only.
Notice:Don’t 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.
Manual Transmission
The gear selector should be in neutral and the parking
brake engaged. Hold the clutch pedal to thefloor
and start the engine. Your vehicle won’t start if the clutch
pedal is not all the way down–that’s a safety feature.
Starting Your VORTEC™2200 L4
Engine
1. With your foot off the accelerator pedal, turn your
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 cause your battery to
be drained much sooner. And the excessive heat
can damage your starter motor. Wait about 15
seconds between each try to help avoid draining
your battery or damaging your starter.
2. If it doesn’t start, wait about 15 seconds and try
again to start the engine by turning the ignition
key to START. Wait about 15 seconds between
each try.
When your engine has run about 10 seconds to
warm up, your vehicle is ready to be driven. Don’t
“race”your engine when it’s cold.
If the weather is below freezing (32°For0°C), let
the engine run for a few minutes to warm up.
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2003 - Sonoma OM

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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2003 - Sonoma OM

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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2003 - Sonoma OM

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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2003 - Sonoma OM

Passing Another Vehicle While Using
Cruise Control
Use the accelerator pedal to increase your speed.
When you take your foot off the pedal, your vehicle will
slow down to the cruise control speed you set earlier.
Using Cruise Control on Hills
How well your cruise control will work on hills depends
upon your speed, load and the steepness of the
hills. When going up steep hills, you may want to step
on the accelerator pedal to maintain your speed.
When going downhill, you may have to brake or shift to
a lower gear to keep your speed down. Of course,
applying the brake takes you out of cruise control. Many
driversnd this to be too much trouble and don’t use
cruise control on steep hills.
Ending Cruise Control
There are two ways to turn off the cruise control:
Step lightly on the brake pedal or push the clutch
pedal, if you have a manual transmission.
If you have an automatic transmission and you
apply your brakes, the cruise control will shut off.
Move the cruise switch to OFF.
Erasing Speed Memory
When you turn off the cruise control or the ignition, your
cruise control set speed memory is erased.
Exterior Lamps
The control on the driver’s side of the instrument panel
operates the exterior lamps.
The exterior lamp control has three positions:
9(Off):Turn the exterior lamps control all the way
counterclockwise to turn off the lamps and put the
system in automatic headlamp mode.
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2003 - Sonoma OM

{CAUTION:
Driving to the top (crest) of a hill at full speed
can cause an accident.There could be a
drop-off, embankment, cliff, or even another
vehicle.You could be seriously injured or
killed.As you near the top of a hill, slow down
and stay alert.
Q:What should I do if my vehicle stalls, or is
about to stall, and I can’t make it up the hill?
A:If this happens, there are some things you should
do, and there are some things you must not do.
First, here’s what youshoulddo:
Push the brake pedal to stop the vehicle and keep
it from rolling backwards. Also, apply the parking
brake.
If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
If your engine has stopped running, you’ll need to
restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission to
PARK (P) (or shift to neutral if your vehicle has
a manual transmission) and restart the engine.Then, shift to REVERSE (R), release the parking
brake, and slowly back down the hill as straight as
possible in REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position.
This way, you’ll be able to tell if your wheels
are straight and maneuver as you back down.
It’s best that you back down the hill with your wheels
straight rather than in the left or right direction.
Turning the wheel too far to the left or right
will increase the possibility of a rollover.
Here are some things youmust notdo if you stall,
or are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting into
NEUTRAL (N) (or pressing the clutch, if you have a
manual transmission) to“rev-up”the engine and
regain forward momentum. This won’t work.
Your vehicle will roll backwards very quickly and
you could go out of control.
Instead, apply the regular brake to stop the
vehicle. Then apply the parking brake. Shift to
REVERSE (R), release the parking brake,
and slowly back straight down.
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2003 - Sonoma OM

Never go downhill with the transmission in
NEUTRAL (N), or with the clutch pedal pressed
down in a manual shift. This is called“free-wheeling”.
Your brakes will have to do all the work and could
overheat and fade.
Q:Am I likely to stall when going downhill?
A:It’s much more likely to happen going uphill. But if
it happens going downhill, here’s what to do.
Stop your vehicle by applying the regular brakes.
Apply the parking brake.
Shift to PARK (P) (or to neutral with the manual
transmission) and, while still braking, restart the
engine.
Shift back to a low gear, release the parking brake,
and drive straight down.
If the engine won’t start, get out and get help.
Driving Across an Incline
Sooner or later, an off-road trail will probably go
across the incline of a hill. If this happens, you have to
decide whether to try to drive across the incline.
Here are some things to consider:
A hill that can be driven straight up or down may be
too steep to drive across. When you go straight up
or down a hill, the length of the wheel base (the
distance from the front wheels to the rear wheels)
reduces the likelihood the vehicle will tumble
end over end. But when you drive across an incline,
the much more narrow track width (the distance
between the left and right wheels) may not prevent
the vehicle from tilting and rolling over. Also,
driving across an incline puts more weight on the
downhill wheels. This could cause a downhill
slide or a rollover.
Surface conditions can be a problem when you
drive across a hill. Loose gravel, muddy spots,
or even wet grass can cause your tires to slip
sideways, downhill. If the vehicle slips sideways,
it can hit something that will trip it (a rock, a rut, etc.)
and roll over.
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2003 - Sonoma OM

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of
Your Vehicle..............................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-5
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.......................5-8
Checking Things Under
the Hood......................................................5-8
Hood Release................................................5-9
Engine Compartment Overview.......................5-10
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid
.........................5-20
Manual Transmission Fluid
.............................5-23
Hydraulic Clutch
...........................................5-24Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-36
Power Steering Fluid.....................................5-37
Windshield Washer Fluid................................5-38
Brakes........................................................5-39
Battery........................................................5-42
Jump Starting...............................................5-43
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
One-Piece Front Turn Signal Lamps................5-52
Two-Piece Front Turn Signal Lamps................5-53
Center High-Mounted Stoplamp (CHMSL).........5-54
Taillamps.....................................................5-55
Replacement Bulbs.......................................5-55
Section 5 Service and Appearance Care
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2003 - Sonoma OM