2003 GMC SIERRA DENALI Owners Manual

Part B: Owner Checks and Services
Listed in this part are owner checks and services
which should be performed at the intervals specified to
help ensure the safety, dependability and emission
control performance of your vehicle.
Be sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
in Part
D.
At Each Fuel Fill
It is important for you or a service station attendant to
perform these underhood checks at each fuel fill.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. See Engine Oil on page 5-13 for further
details.
Engine Coolant Level Check Windshield Washer Fluid Level Check
Check
the windshield washer fluid level in the windshield
washer tank and add the proper fluid
if necessary.
See
Windshield Washer Fluid on page 5-38 for further
details.
At Least Once a Month
Tire Inflation Check
Make sure tries are inflated to the correct pressures.
Don’t forget to check your spare tire. See
Tires on
page 5-61
for further details.
Cassette Tape Player Service
Clean cassette tape player. Cleaning should be done
every
50 hours of tape play. See Audio System(s)
on page 3-61
for further details.
Check the engine coolant level and add
DEX-COOL@
coolant mixture if necessary. See Engine Coolant
on page
5-24 for further details.
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At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts.
If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced.
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 5-88.
Spare Tire Check
At least twice a year, after the monthly inflation check of
the spare tire determines that the spare is inflated to
the correct tire inflation 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
wrenchhatchet to tighten the cable. See
Changing a Flat
Tire on page 5-69.
Weatherstrip
Silicone grease on
longer, seal better,
Lubrication
weatherstrips will make them last
and not stick or squeak. Apply
silicone grease with a clean cloth. During very -cold,
damp weather more frequent application may be
required. See
Part D: Recommended Fluids and
lubricants on page
6- 16.
Automatic Transmission Check
Check the transmission fluid level; add if needed. See
Automatic Transmission Fluid on page 5-27. A fluid 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
specified 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.
6-1 1

Starter Switch Check Automatic Transmission Shift Lock
Contr-l System Check
When you are doing this check, the vehicle
could move suddenly.
If it does, you or others
could be injured. Follow the steps below.
1
1.
2.
3.
Before you start, be sure you have enough room
around the vehicle.
Firmly apply both the parking brake and the regular
brake. See
Parking Brake on page 2-22 if
necessary.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately
if it starts.
Try
to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL
(N).
If the starter works in any other position, your
vehicle needs service.
I
_/hen you are doing _.. check, tl vel le
could move suddenly.
If it does, you or others
could be injured.
Follow the steps below.
I
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. See Parking Brake
on page 2-22 if necessary.
Be ready
to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the key to the RUN
position, but don’t start the engine. Without applying
the regular brake, try
to move the shift lever out
of PARK (P) with normal effort.
If the shift lever
moves out of PARK (P), your vehicle needs service.
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Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK in each shift lever position.
* The key should turn to LOCK only when the
The key should come out only in LOCK.
shift lever
is in PARK (P).
Parking Brake and Automatic
Transmission Park (P) Mechanism
A. le1 , ..
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there
is room in front of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move. Park on a
fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set the
parking brake.
@ To check the parking brake’s holding ability: With
the engine running and transmission in
NEUTRAL
(N), slowly remove foot pressure from the regular
brake pedal.
Do this until the vehicle is held by the
parking brake only.
ability: With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
To check the PARK (P) mechanism’s holding
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
6-1 3

Part C: Periodic Maintenance
Inspections
Listed in this part are inspections and services which
should be performed at least twice a year (for instance,
each spring and fall).
You should let your dealer’s
service department or other qualified service center do
these jobs. Make sure any necessary repairs are
completed at once.
Proper procedures to perform these services may be
found in a service manual. See
Service Publications
Ordering lnformation on page
7- 10.
Steering and Suspension Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system. Look for broken, damaged,
missing or out-of-position parts as well as open seams,
holes, loose connections or other conditions which
could cause a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. See
Engine Exhaust
on page
2-26.
Fuel System Inspection
Inspect the complete fuel system for damage or leaks.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they
are cracked, swollen or deteriorated. Inspect
all pipes,
fittings and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser.
To help ensure proper operation, a pressure test of
the cooling system and pressure cap is recommended
at least once a year.
6-1 4

Transfer Case and Front Axle
(All-Wheel Drive) Inspection
Every 12 months, or at engine oil change intervals,
check front axle and transfer case and add lubricant
when necessary.
A fluid loss could indicate a problem.
Check and have it repaired,
if needed. Check vent
hose at transfer case for kinks and proper installation.
Brake System Inspection
Inspect the complete system. Inspect brake lines and
hoses for proper hook-up, binding, leaks, cracks,
chafing, etc; Inspect
disc brake pads for wear and rotors
for surface condition. Inspect other brake parts,
including calipers, parking brake, etc. You may need to
have your brakes inspected more often if your driving
habits or conditions result in frequent braking.
6-1 5

Part D: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number or specification may be obtained from your
dealer.
Engine Oil
Engine Coolant
Hydraulic Brake
System
Windshield
Washer Solvent
Power Steering
System
~~
Automatic
Transmission Fluid/Lubricant
Engine oil with the American
Petroleum Institute Certified for
Gasoline Engines starburst symbol
of the proper viscosity. To determine
the preferred viscosity for your
vehicle's engine, see
Engine Oil on
Daae
5- 13.
50/50 mixture of clean, drinkable
water and use only DEX-COOL
Coolant. See
Engine Coolant on
page
5-24.
Delco Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
GM Optikleen Washer Solvent or
equivalent.
GM Power Steering Fluid (GM Part
No.
U.S. 1052884, in Canada
993294, or equivalent).
DEXRON-Ill Automatic Transmission
Fluid. Usage
FluWLubricant
Multi-Purpose Lubricant, Superlube
Key Lock
Canada 10953474. or eauivalent). Cylinders (GM Part No. U.S. 12346241, in
Floor Shift
Linkage
Chassis
Lubrication Lubriplate
Lubricant Aerosol (GM
Part No.
US. 12346293, in Canada
' 992723, or equivalent) or lubricant
meeting requirements of NLGl #2
Category LB or GC-LB.
Chassis Lubricant (GM Part
No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGl #2,
Cateaow LB or GC-LB.
SAE 75W-90 Synthetic Axle
Lubricant (GM Part No.
U.S.
Front Axle 12378261, in Canada 10953455) or
equivalent meeting GM Specification
99861 15.
Synthetic Axle Lubricant; use only
Rear Axle
88901362).
Do not add friction
(Steerable) GM Part
No. 12378557
(in Canada
modifier.
Transfer Case
I Fluid.
DEXRON-Ill Automatic Transmission
Chassis Lubricant (GM Part No.
U.S. 12377985,
in Canada Rear Driveline
meeting requirements of NLGI #2, Center Spline 88901242, or equivalent) or lubricant
CateqorV LB or GC-LB.
6-1 6

Usage
Front Axle
Propshaft Spline
Hood Hinges Body Door
Hinge Pins,
Tailgate Hinge
and Linkage, Folding Seat
and Fuel Door
Hinge
-
FluidlLubricant ~
Spline Lubricant, Special Lubricant
(GM Part
No. U.S. 12345879, in
Canada 1095351 1) or lubricant
meeting
requirements of GM
9985830.
Multi-Purpose Lubricant, Superlube
(GM Part
No. U.S. 12346241, in
Canada 10953474,
or equivalent).
Multi-Purpose Lubricant, Superlube
(GM Part
No. U.S. 12346241, in
Canada 10953474, or equivalent). Weatherstrip
Shperlube (GM Part
No. U.S.
Squeaks 12371287, in Canada 10953437, or
eauivalent).
6-1
7