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Service and Maintenance 449
Footnotes—Maintenance
Schedule Additional Required
Services - Severe
(1) Or every two years, whichever
comes first. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy
traffic, poor air quality, areas with
high dust levels or are sensitive to
environmental allergens. Filter
replacement may also be needed if
you notice reduced airflow, windows
fogging up, or odors. Your local GM
Service location can help you
determine when it is the right time to
replace your filter.
(2) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0344.
(3) Visually check all fuel and vapor
lines and hoses for proper
attachment, connection, routing, and
condition.
(4) Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can overcome the seals and
contaminate the fluid. Contaminated
fluid will decrease the life of the
transfer case and/or drive axles and
should be replaced.
(5)
Or every five years, whichever
comes first. See Cooling System
0 346.
(6) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.
(7) Replace brake fluid every five
years. See Brake Fluid 0357.
(8) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0364.
(9) Or every 10 years, whichever
comes first. See Gas Strut(s)0365.
(10) Replace air conditioning
desiccant every seven years.Special Application
Services
. Vehicles with Dual Wheels:
Check dual wheel nut torque at
160, 1 600, and 10 000 km (100,
1,000, and 6,000 mi) of driving.
Repeat this service whenever a
tire/wheel is serviced or
removed.
. Severe Commercial Use
Vehicles Only: Lubricate chassis
components every oil change.
. Have underbody flushing service
performed. See “Underbody
Maintenance” inExterior Care
0 429.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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450 Service and Maintenance
Additional
Maintenance and Care
Your vehicle is an important
investment and caring for it properly
may help to avoid future costly
repairs. To maintain vehicle
performance, additional
maintenance services may be
required.
It is recommended that your dealer
perform these services—their
trained dealer technicians know
your vehicle best. Your dealer can
also perform a thorough
assessment with a multi-point
inspection to recommend when your
vehicle may need attention.
The following list is intended to
explain the services and conditions
to look for that may indicate
services are required.
Battery
The 12-volt battery supplies power
to start the engine and operate any
additional electrical accessories. .
To avoid break-down or failure to
start the vehicle, maintain a
battery with full cranking power.
. Trained dealer technicians have
the diagnostic equipment to test
the battery and ensure that the
connections and cables are
corrosion-free.
Belts
. Belts may need replacing if they
squeak or show signs of
cracking or splitting.
. Trained dealer technicians have
access to tools and equipment
to inspect the belts and
recommend adjustment or
replacement when necessary.
Brakes
Brakes stop the vehicle and are
crucial to safe driving.
. Signs of brake wear may include
chirping, grinding, or squealing
noises, or difficulty stopping. .
Trained dealer technicians have
access to tools and equipment
to inspect the brakes and
recommend quality parts
engineered for the vehicle.
Fluids
Proper fluid levels and approved
fluids protect the vehicle’s systems
and components. See
Recommended Fluids and
Lubricants 0453 for GM approved
fluids.
. Engine oil and windshield
washer fluid levels should be
checked at every fuel fill.
. Instrument cluster lights may
come on to indicate that fluids
may be low and need to be
filled.
Hoses
Hoses transport fluids and should
be regularly inspected to ensure
that there are no cracks or leaks.
With a multi-point inspection, your
dealer can inspect the hoses and
advise if replacement is needed.
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Service and Maintenance 453
Recommended Fluids, Lubricants, and Parts
Recommended Fluids and Lubricants
This maintenance section applies to vehicles with a gasoline engine. If the vehicle has a diesel engine, see
“Recommended Fluids and Lubricants”in the Duramax diesel supplement.
Fluids and lubricants identified below by name, part number, or specification can be obtained from your dealer.
Usage Fluid/Lubricant
Automatic Transmission (6-Speed Transmission) DEXRON-VI Automatic Transmission Fluid.
Automatic Transmission (8-Speed Transmission) DEXRON-HP Automatic Transmission Fluid.
Automatic Transmission (10-Speed Transmission) DEXRON ULV Automatic Transmission Fluid.
Chassis Lubrication Chassis Lubricant (GM Part No. 12377985, in Canada 88901242) or lubricant meeting requirements of NLGI #2, Category LB or GC-LB.
Engine Coolant 50/50 mixture of clean, drinkable water and use only DEX-COOL coolant. SeeCooling System 0346.
Engine Oil Engine oil meeting the dexos1 specification of the proper SAE viscosity grade. ACDelco dexos1 full synthetic is recommended. See Engine Oil
0 339.
Front and Rear Axle Driveshaft Splines Spline Lubricant, Special Lubricant (GM Part No. 19257121, in
Canada 19257122).
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Service and Maintenance 455
Maintenance Replacement Parts
Replacement parts identified below by name, part number, or specification can be obtained from your dealer.
If the vehicle has a diesel engine, see the Duramax diesel supplement.Part GM Part Number ACDelco Part Number
Engine Air Cleaner/Filter With high capacity air cleaner 84121219 A3244C
Without high capacity air cleaner 84121217 A3246C
Oil Filter
2.7L L4 55495106 PF66
4.3L V6 12690385 PF63E
5.3L V8 12690385 PF63E
6.2L V8 12690385 PF63E
6.6L V8 12690385 PF63E
Passenger Compartment Air Filter 13508023 CF185
Spark Plugs 2.7L L4 12688094 41-106-IP
4.3L V6 12622441 41-114
5.3L V8 12622441 41-114
6.2L V8 12622441 41-114
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458 Technical Data
Technical Data
Vehicle Identification
Vehicle IdentificationNumber (VIN) . . . . . . . . . . . . . . . 458
Service Parts Identification . . . 458
Vehicle Data
Capacities and Specifications . . . . . . . . . . . . . . . 459
Engine Drive Belt Routing . . . . 462
Vehicle Identification
Vehicle Identification
Number (VIN)
This legal identifier is in the front
corner of the instrument panel, on
the driver side of the vehicle. It can
be seen through the windshield from
outside. The Vehicle Identification
Number (VIN) also appears on the
Vehicle Certification and Service
Parts labels and certificates of title
and registration.
Engine Identification
The eighth character in the VIN is
the engine code. This code
identifies the vehicle's engine,
specifications, and replacement parts. See
“Engine Specifications”
under Capacities and Specifications
0 459 for the vehicle's engine code.
Service Parts
Identification
There may be a large barcode on
the certification label on the center
pillar that you can scan for the
following information:
.
Vehicle Identification
Number (VIN)
. Model designation
. Paint information
. Production options
If there is not a large barcode on
this label, then you will find this
same information on a label inside
of the glove box.
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Technical Data 459
Vehicle Data
Capacities and Specifications
The following approximate capacities are given in metric and English conversions. SeeRecommended Fluids and
Lubricants 0453.
If the vehicle has a diesel engine, see the Duramax diesel supplement.
Application Capacities
Metric English
Air Conditioning Refrigerant For the air conditioning system refrigerant type and charge amount, see the refrigerant label under thehood. See your dealer for more information.
Engine Cooling System*
2.7L L4 Engine –1500 Series 11.8 L 12.4 qt
4.3L V6 Engine –1500 Series 11.5 L 12.2 qt
5.3L V8 Engine –1500 Series (L82) 12.8 L 13.5 qt
5.3L V8 Engine –1500 Series (L84) 13.1 L 13.8 qt
6.2L V8 Engine –1500 Series 12.6 L 13.3 qt
6.6L V8 Gas Engine –2500 Series and 3500 Series (L8T) 15.1 L 15.9 qt
Engine Oil with Filter
2.7L L4 Engine –1500 Series 5.7 L 6.0 qt
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460 Technical Data
ApplicationCapacities
Metric English
4.3L V6 Engine –1500 Series 5.7 L 6.0 qt
5.3L V8 Engine –1500 Series (L84) 7.6 L 8.0 qt
6.2L V8 Engine –1500 Series 7.6 L 8.0 qt
6.6L V8 Gas Engine –2500 Series and 3500 Series 7.6 L 8.0 qt
Fuel Tank 1500 Series Standard and Short Box (4WD Gas and
Diesel) 90.8 L 24.0 gal
1500 Series Standard and Short Box (2WD Diesel) 83.3 L 22.0 gal
1500 Series Long Box 106.0 L 28.0 gal
2500 Series and 3500 Series Standard Box (Except
Double Cab Diesel) 136.3 L 36.0 gal
2500 Series and 3500 Series Standard Box (Double Cab
Diesel) 111.3 L 29.4 gal
2500 Series and 3500 Series Long Box (Except Regular
Cab Diesel) 136.3 L 28.0 gal
2500 Series and 3500 Series Long Box (Regular Cab
Diesel) 106.0 L 28.0 gal
3500 Series Chassis Cab –Front Tank 89.0 L 23.5 gal
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Technical Data 461
ApplicationCapacities
Metric English
3500 Series Chassis Cab –Rear Tank 151.4 L 40.0 gal
Transfer Case Fluid (1500 Series Only) 1.5 L 1.6 qt
Transfer Case Fluid (2500 and 3500 Series Only) 2.3 L 2.4 qt
Wheel Nut Torque 190 Y140 lb ft
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this
manual. Recheck fluid level after filling.
*Engine cooling system capacity values are based on the entire cooling system and its components.
Engine Specifications
Engine VIN CodeSpark Plug Gap
2.7L L4 (L3B) K0.65–0.75 mm (0.026–0.030 in)
4.3L V6 (LV3) H0.95–1.10 mm (0.037–0.043 in)
5.3L V8 (L82) F0.95–1.10 mm (0.037–0.043 in)
5.3L V8 (L84) D0.95–1.10 mm (0.037–0.043 in)
6.2L V8 (L87) L0.95–1.10 mm (0.037–0.043 in)
6.6L V8 (L8T) 70.95–1.10 mm (0.037–0.043 in)
Spark plug gaps are preset by the manufacturer. Re-gapping the spark plug is not recommended and can damage
the spark plug.