2008 GMC YUKON XL engine

The proper replacement parts, uids, and lubricants to
use are listed inRecommended Fluids and Lubricants
on page 6-13andMaintenance Replacement Parts
on page 6-15. When your vehicle is serviced, make sure
these are used. All parts should be replaced and all
necessary repairs done before you or anyone else
drives the vehicle. We recommend the use of genuine
parts from your dealer/retailer.
Scheduled Maintenance
When the CHANGE ENGINE OIL SOON message
comes on, it means that service is required for your
vehicle. Have your vehicle serviced as soon as possible
within the next 600 miles (1 000 km). It is possible
that, if you are driving under the best conditions, the
engine oil life system may not indicate that vehicle
service is necessary for over a year. However, your
engine oil and lter must be changed at least once a
year and at this time the system must be reset.
Your dealer/retailer has trained service technicians who
will perform this work using genuine parts and reset
the system.If the engine oil life system is ever reset accidentally,
you must service your vehicle within 3,000 miles
(5 000 km) since your last service. Remember to reset
the oil life system whenever the oil is changed. See
Engine Oil Life System on page 5-18for information on
the Engine Oil Life System and resetting the system.
When the CHANGE ENGINE OIL SOON message
appears, certain services, checks, and inspections are
required. Required services are described in the
following for “MaintenanceI” and “MaintenanceII.”
Generally, it is recommended that your rst service be
MaintenanceI, your second service be MaintenanceII,
and that you alternate MaintenanceIand MaintenanceII
thereafter. However, in some cases, MaintenanceII
may be required more often.
MaintenanceI— Use MaintenanceIif the CHANGE
ENGINE OIL SOON message comes on within
10 months since the vehicle was purchased or
MaintenanceIIwas performed.
MaintenanceII— Use MaintenanceIIif the previous
service performed was MaintenanceI. Always use
MaintenanceIIwhenever the message comes on
10 months or more since the last service or if the
message has not come on at all for one year.
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Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-15. Reset oil life system.
SeeEngine Oil Life System on page 5-18.An Emission Control Service.••
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter or change indicator (if equipped). If necessary,
replace lter. SeeEngine Air Cleaner/Filter on page 5-19.See footnote (l).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-78and “Tire Wear Inspection” inAt Least Once a Month on
page 6-10.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid
as needed.••
Perform any needed additional services. See “Additional Required Services”
in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
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Additional Required Services
The following services should be performed at the rst maintenance service (IorII) after the indicated miles
(kilometers) shown for each item.
Additional Required Services
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Inspect fuel system for damage or leaks.• •••••
Inspect exhaust system for loose or
damaged components.• •••••
Vehicles without a lter restriction
indicator: Replace engine air cleaner
lter. SeeEngine Air Cleaner/Filter on
page 5-19.•••
Change automatic transmission uid and
lter (severe service).See footnote (h).•••
Change automatic transmission uid and
lter (normal service).•
Four-wheel drive: Change transfer case
uid.See footnote (g).•••
Inspect evaporative control system.An
Emission Control Service. See footnotes
† and (k).•••
Replace spark plugs and inspect spark
plug wires.An Emission Control Service.•
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Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Engine cooling system service (or every
ve years, whichever occurs rst).An
Emission Control Service. See
footnote (i).•
Inspect engine accessory drive belt.An
Emission Control Service. See
footnote (m).•
Maintenance Footnotes
†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.
#Lubricate the front suspension, steering linkage, and
parking brake cable guides. Control arm ball joints
on 2500 series vehicles require lubrication but should
not be lubricated unless their temperature is 10°F
(−12°C) or higher, or they could be damaged. Control
arm ball joints on 1500 series vehicles are
maintenance-free.(a)Visually 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.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose, or missing parts,
signs of wear, or lack of lubrication. Inspect power
steering lines and hoses for proper hook-up, binding,
leaks, cracks, chafing, etc. Visually check constant
velocity joints, rubber boots, and axle seals for leaks.
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(c)Visually inspect hoses and have them replaced if they
are cracked, swollen, or deteriorated. Inspect all pipes,
fittings, and clamps; replace with genuine parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. See Windshield Wiper Blade Replacement on
page 5-62andWindshield, Backglass, and Wiper
Blades on page 5-113 for more information.
(e)Make sure the safety belt reminder light and safety
belt assemblies 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 see Checking
the Restraint Systems on page 1-92.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer liftgate handle pivot
points, rear door detent link, roller mechanism, liftgate
handle pivot points, latch bolt, fuel door hinge, cargo
door hinge, locks, and folding seat hardware. More
frequent lubrication may be required when exposed to
a corrosive environment.Applying silicone grease on weatherstrips with a clean
cloth will make them last longer, seal better, and
not stick or squeak.
(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission fluid and filter 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.
(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-28
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)Inspect system. Check all fuel and vapor lines and
hoses for proper hook-up, routing, and condition. Check
that the purge valve works properly, if equipped.
Replace as needed.
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(l)If you drive regularly under dusty conditions, inspect
the filter at each engine oil change.
(m)Visually inspect belt for fraying, excessive cracks,
or obvious damage. Replace belt if necessary.
Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability, and emission control performance of your
vehicle. Your dealer/retailer can assist you with these
checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by your warranty.
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-15.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-28.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer uid reservoir and add the proper uid if
necessary.
6-9

At Least Once a Month
Tire Ination Check
Inspect your vehicle’s tires and make sure they are
inated to the correct pressures. Do not forget to check
the spare tire. SeeInflation - Tire Pressure on
page 5-72. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-88.
Tire Wear Inspection
Tire rotation may be required for high mileage highway
drivers prior to the Engine Oil Life System service
notication. Check the tires for wear and, if necessary,
rotate the tires. SeeTire Inspection and Rotation on
page 5-78.
At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-43.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle
should start only in PARK (P) or NEUTRAL (N). If
the vehicle starts in any other position, contact your
dealer/retailer for service.
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Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
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. SeeParking Brake
on page 2-43.
Be ready to apply the regular brake immediately if
the vehicle begins to move.3. With the engine off, turn the ignition to ON/RUN,
but do not 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), contact your dealer/retailer
for service.Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition to LOCK/OFF in each shift lever position.
The ignition should turn to LOCK/OFF only
when the shift lever is in PARK (P).
The ignition key should come out only in
LOCK/OFF.
Contact your dealer/retailer if service is required.
6-11