2003 GMC YUKON DENALI service interval

A temporary solution to hotter transmission operating
temperatures may be
to let the transmission cool down.
If the transmission is operated at higher temperatures
on a frequent basis, see
Scheduled Maintenance
on page
6-5 for the proper transmission maintenance
intervals.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with
a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD
II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping
to produce a cleaner
environment. The Check Engine light comes on
to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage
to your vehicle. This system is also
designed to
assist your service technician in correctly
diagnosing any malfunction.
Notice: If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice: Modifications made to the engine,
transmission, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modifications to these systems could lead to costly
repairs not covered by your warranty. This may
also result
in a failure to pass a required Emission
Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light doesn’t come on, have it
repaired. This light will also come on during
a
malfunction in one of two ways:
Light Flashing - A misfire condition has been
detected.
A misfire increases vehicle emissions
and may damage the emission control system on
your vehicle. Dealer or qualified service center
diagnosis and service may be required.
3-38

Notice: Don’t let anyone tell you that underinflation
or overinflation is all right. It’s not. If your tires
don’t have enough air (underinflation), you can get
the following:
Too much flexing
Too much heat
0 Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overinflation), you
can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell
if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (12,500 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment.
Also
check for damaged tires or wheels. See When It Is Time
for New Tires on page
5-58 and Wheel Replacement
on page
5-61 for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If
it moves,
use the wheel wrench and jack handle extensions
to
tighten the cable. See Changing a Flat Tire on
page 5-63.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle.
The first rotation
is the most important. See “Part
A: Scheduled
Maintenance Services,” in Section
6, for scheduled
rotation intervals.
5-56

Part A: Scheduled Maintenance
Services
This part contains engine oil and chassis lubrication
scheduled maintenance which explains the engine oil life
system and how it indicates when
to change the
engine oil and filter. Lubricate chassis components with
each oil change.
Also, listed are scheduled maintenance
services which are to be performed at the mileage
intervals specified.
Using Your Maintenance Schedule
We at General Motors want to help you keep your
vehicle in good working condition. But we don’t know
exactly how you’ll drive it. You may drive very short
distances only a few times a week. Or you may drive
long distances all the time in very hot, dusty weather.
You may use your vehicle in making deliveries. Or
you may drive it to work,
to do errands or in many
other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements.
So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your dealer. This part tells you
the maintenance services you should
have done and when you should schedule them.
When you go
to your dealer for your service needs,
you’ll know that GM-trained and supported service
people will perform the work using genuine GM parts.
The proper fluids and lubricants
to use are listed in
Part
D. Make sure whoever services your vehicle uses
these.
All parts should be replaced and all necessary
repairs done before you or anyone else drives the
vehicle.
This schedule is for vehicles that:
carry passengers and cargo within recommended
limits. You will find these limits on your vehicle’s
Certificationflire label. See Loading Your Vehicle
on
page 4-44.
are driven on reasonable road surfaces within legal
driving limits.
are driven off-road in the recommended manner.
See Operating Your All- Wheel-Drive Vehicle
Off
Paved Roads on page 4- 16.
use the recommended fuel. See Gasoline Octane
on page 5-5.
6-4

Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(1 66 000 km) should be repeated after 100,000 miles
(166
000 km) at the same intervals for the life of
this vehicle. The services shown at
150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles
(240 000 km) for the life of this
vehicle.
See Part B: Owner Checks and Services
on page 6- 10
and Part C: Periodic Maintenance Inspections on
page 6- 14.
Footnotes
t The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle
s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
+ A good time to check your brakes is during tire
rotation. See Brake System Inspection
on page 6-14.
Engine Oil and Chassis Lubrication
Scheduled Maintenance
Change engine oil and filter as indicated by the GM
Oil Life System (or every 12 months, whichever
occurs first). Reset the system.
Your vehicle has a computer system that lets you know
when
to change the engine oil and filter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system
to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE
OIL message will
come on. Change your oil as soon as possible within
the next two times you stop for fuel.
It is possible that, if
you are driving under the best conditions, the oil life
system may not indicate that an oil change is necessary
for over a year. However, your engine oil and filter
must be changed at least once a year and at this time
the system must be reset.
It is also important to
check your oil regularly and keep it at the proper level.
6-5

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
Check the engine coolant level and add DEX-COOL@
coolant mixture
if necessary. See Engine Coolant
on page 5-22 for further details.
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 5-34 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 5-55 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 3-58 for further details.
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.
6-1 0

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 Information on page
7- IO.
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 2-29.
Fuel System Inspection
Engine Cooling System Inspection
Inspect the complete fuel system for damage or leaks.
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.
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 4