automatic transmission GMC SIERRA 2003 User Guide

Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmissionuid (don’t overll),
engine oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help yound them quickly. If
you’re trailering, it’s a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
4-60
2003 - Sierra Denali

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.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under
the Hood....................................................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid.........................5-20
Engine Coolant.............................................5-23
Coolant Surge Tank Pressure Cap..................5-26
Engine Overheating.......................................5-26
Cooling System............................................5-29Engine Fan Noise.........................................5-34
Power Steering Fluid.....................................5-34
Windshield Washer Fluid................................5-35
Brakes........................................................5-36
Battery........................................................5-39
Jump Starting...............................................5-40
All-Wheel Drive..............................................5-45
Rear Axle.......................................................5-46
Front Axle......................................................5-47
Bulb Replacement..........................................5-48
Halogen Bulbs..............................................5-48
Headlamps..................................................5-48
Front Turn Signal, Sidemarker and
Daytime Running Lamps.............................5-49
Roof Marker Lamps......................................5-51
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp.......................................5-52
Pickup Box Identification and Fender
Marker Lamps...........................................5-54
Taillamps.....................................................5-54
Replacement Bulbs.......................................5-55
Windshield Wiper Blade Replacement
..............5-56
Section 5 Service and Appearance Care
5-1
2003 - Sierra Denali

A. Engine Air Cleaner/Filter
B. Coolant Surge Tank
C. Air Cleaner/Filter Restriction Indicator
D. Engine Oil Dipstick
E. Engine Oil Fill Cap
F. Automatic Transmission Dipstick
G. Fan
H. Remote Negative (−) Terminal (GND)
I. Remote Positive (+) Terminal
J. Power Steering Fluid Reservoir
K. Brake Fluid Reservoir
L. Underhood Fuse Block
M. Battery
N. Windshield Washer Fluid Reservoir
Engine Oil
If the CHECK OIL LEVEL light appears on the
instrument cluster, it means you need to check your
engine oil level right away. For more information,
see“CHECK OIL LEVEL”underDIC Warnings and
Messages on page 3-51.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It’s a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick has a yellow looped handle and
is located on the passenger’s side of the vehicle.
SeeEngine Compartment Overview on page 5-12for
more information on location.
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don’t, the oil
dipstick might not show the actual level.
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
5-13
2003 - Sierra Denali

Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change thefluid andfilter every
100,000 miles (166 000 km).
SeePart A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too littlefluid can damage
your transmission. Too much can mean that some
of thefluid could come out and fall on hot engine
part or exhaust system parts, starting afire.
Too littlefluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmissionfluid.
Wait at least 30 minutes before checking the
transmissionfluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic–especially in hot weather.
•While pulling a trailer.
To get the right reading, thefluid should be at normal
operating temperature, which is 180°Fto200°F
(82°Cto93°C).
5-20
2003 - Sierra Denali

3. Check both sides of the dipstick, and read the lower
level. Thefluid level must be in the COLD area,
below the cross-hatched area, for a cold check or in
the HOT area or cross-hatched area for a hot
check.
4. If thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-15.
Addfluid only after checking the transmissionfluid while
it is hot. (A cold check is used only as a reference.) If
thefluid level is low, add only enough of the properfluid
to bring the level up to the HOT area for a hot check.
It doesn’t take muchfluid, generally less than one
pint (0.5 L).Don’t overfill.
Notice:We recommend you use onlyfluid labeled
DEXRON
®-III, becausefluid with that label is
made especially for your automatic transmission.
Damage caused byfluid other than DEXRON
®-III is
not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described under“How to Check”.
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
5-22
2003 - Sierra Denali

Jump Starting
If your battery (or batteries) has run down, you may
want to use another vehicle and some jumper cables to
start your vehicle. Be sure to follow the steps below
to do it safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
•They contain acid that can burn you.
•They contain gas that can explode or
ignite.
•They contain enough electricity to
burn you.
If you don’t follow these steps exactly, some
or all of these things can hurt you.Notice:Ignoring these steps could result in costly
damage to your vehicle that wouldn’t be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
won’t work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other system isn’t a 12-volt system
with a negative ground, both vehicles can be
damaged.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection you don’t want. You wouldn’t be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brakefirmly on both vehicles involved in
the jump start procedure. Put the automatic
transmission in PARK (P) before setting the parking
brake. If you have a four-wheel-drive vehicle, be
sure the transfer case is in a drive gear not in
NEUTRAL.
5-40
2003 - Sierra Denali

Fuses Usage
IGN 1 Ignition Relay
PCM 1 Powertrain Control Module
ETC/ECMElectronic Throttle Control,
Electronic Brake Controller
IGN EInstrument Panel Cluster, Air
Conditioning Relay, Turn
Signal/Hazard Switch, Starter
Relay
RTD Ride Control
TRL B/U Backup Lamps Trailer Wiring
PCM BPowertrain Control Module,
Fuel Pump
F/PMP Fuel Pump (Relay)
B/U LPBack-up Lamps, Automatic
Transmission Shift Lock
Control System
RR DEFOG Rear Window Defogger
HDLP-HI Headlamp High Beam Relay
PRIME Not Used
02B Oxygen Sensors
SIRSupplemental Inflatable
Restraint System
FRT PARKFront Parking Lamps,
Sidemarker Lamps
DRLDaytime Running Lamps
(Relay)Fuses Usage
SEO IGN Rear Defog Relay
TBC IGN1 Truck Body Controller Ignition
HI HDLP-LT High Beam Headlamp-Left
LH HID Not Used
DRL Daytime Running Lamps
IPC/DICInstrument Panel
Cluster/Driver Information
Center
HVAC/ECAS Climate Control Controller
CIG LTR Cigarette Lighter
HI HDLP-RT High Beam Headlamp-Right
HDLP-LOW Headlamp Low Beam Relay
A/C COMP Air Conditioning Compressor
A/C COMPAir Conditioning Compressor
Relay
RR WPR Not Used
RADIO Audio System
SEO B1Mid Bussed Electrical Center,
Rear Heated Seats,
HomeLink
LO HDLP-LT Headlamp Low Beam-Left
BTSIBrake Transmission Shift
Interlock System
CRANK Starting System
LO HDLP-RT Headlamp Low Beam-Right
5-98
2003 - Sierra Denali

❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
❑Replace fuelfilter.An Emission Control Service.
(See footnote†.)
37,500 Miles (62 500 km)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
45,000 Miles (75 000 km)
❑Inspect engine air cleanerfilter change indicator.
If necessary, replace thefilter. If vehicle is driven
in dusty/dirty conditions, inspectfilter change
indicator at every engine oil change. SeeEngine Air
Cleaner/Filter on page 5-18for more information.
An Emission Control Service. (See footnote†.)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.❑Rotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
50,000 Miles (83 000 km)
❑Change automatic transmissionfluid andfilter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the fluid and filter at 100,000 miles
(166 000 km).
52,500 Miles (87 500 km)
❑Check rear/front axle uid level and add uid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
6-7
2003 - Sierra Denali

❑Check rear/front axleuid level and adduid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Replace fuellter.An Emission Control Service.
(See Footnote†.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
97,500 Miles (162 500 km)
❑Check rear/front axleuid level and adduid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
100,000 Miles (166 000 km)
❑Inspect spark plug wires.An Emission Control
Service.
❑Replace spark plugs.An Emission Control Service.❑Change automatic transmissionuid andlter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
❑If you haven’t used your vehicle under severe service
conditions listed previously and, therefore, haven’t
changed your automatic transmissionuid, change
both theuid andlter.
❑Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service.
150,000 Miles (240 000 km)
❑Drain,ush and rell cooling system (or every
60 months since last service, whichever occursrst).
SeeEngine Coolant on page 5-23for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.An Emission Control Service.
❑Inspect engine accessory drive belt.An Emission
Control Service.
6-9
2003 - Sierra Denali

Also look for any opened or broken air bag coverings,
and have them repaired or replaced. (The air bag
system does not need regular maintenance.)
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace
blade inserts that appear worn or damaged or that
streak or miss areas of the windshield. Also see
Cleaning the Outside of Your Vehicle on page 5-85.
Spare Tire Check
At least twice a year, after the monthly ination check of
the spare tire determines that the spare is inated to
the correct tire ination pressure, make sure that
the spare tire is stored securely. Push, pull, and then try
to rotate or turn the tire. If it moves, use the wheel
wrench/ratchet to tighten the cable. SeeChanging a Flat
Tire on page 5-65.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. SeePart D: Recommended Fluids and
Lubricants on page 6-15.
Automatic Transmission Check
Check the transmissionuid level; add if needed. See
Automatic Transmission Fluid on page 5-20.Auid loss
may indicate a problem. Check the system and repair
if needed.
At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specied in Part D.
Body Lubrication Service
Lubricate all body door hinges, hood latch assembly,
secondary latch, pivots, spring anchor, release
pawl, tailgate hinge, tailgate linkage, tailgate handle
pivot points, latch bolt, fuel door hinge, locks and folding
seat hardware. Part D tells you what to use. More
frequent lubrication may be required when exposed to a
corrosive environment.
6-11
2003 - Sierra Denali