Scheduled Maintenance
Supplements
If your vehicle has a Caterpillar®diesel engine, your
owner’s manual is supplemented by the Caterpillar®
Diesel Engine Operation & Maintenance Manual. If your
vehicle has an Allison transmission, your owner’s
manual is supplemented by an Allison
Transmission
®Operator’s Manual. Always refer to these
manuals for related maintenance services.
Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown after 100,000 miles
(166 000 km) should be repeated at the same miles (km)
after those intervals for the life of this vehicle.Gasoline engine vehicles and some DURAMAX
®diesel
engine vehicles have a computer that lets you know
when to change your engine oil. This is not based
on mileage, but on engine operation and engine
temperature. When the computer has calculated that the
oil needs changing, the Engine Oil Life System will
indicate that a change is necessary. SeeEngine Oil Life
System (Gasoline Engine) on page 5-29orEngine Oil
Life System (DURAMAX
®Diesel) on page 5-31or
Engine Oil Life System (Caterpillar®Diesel Engine) on
page 5-32.
The “Footnotes” at the end of this Maintenance
Schedule further explain maintenance services.
SeeService Publications Ordering Information on
page 7-8.
100 Miles (160 km)
❑Wheel stud nut service.(36)
1,000 Miles (1 600 km)
❑Wheel stud nut service.(36)
❑Rear axle air shift motor service.(10)
6-5
(14)= Adjust tire pressures as indicated on the Gross
Vehicle Weight (GVW) Rating label for optimum tire life.
SeeTires on page 5-70for further details. Check
tires for excessive or abnormal wear or damage. Also
check for damaged wheels. Replace wheels and/or tires
as needed.
(15)= Check spring-to-axle U-bolts and shackle bolts
for proper torque. See the service manual for torque
sequence and specifications. When parts are replaced,
the torque must be checked and adjusted more often
during the first 6,000 miles (10 000 km). Check torque at
500 miles (800 km) and 2,000 miles (3 000 km) after
first use of parts.
(16)= Check complete exhaust system and cab areas
near the exhaust system for broken, damaged,
missing, or out-of-position parts. Also inspect for open
seams, holes, loose connections, or other conditions
which could let exhaust fumes seep into the driver
compartment. Needed repairs should be made at once.
To help maintain system integrity, replace exhaust
pipes whenever a new muffler is put on.
(17)= Check all gasoline engine drive belts for cracks,
fraying, and wear. Replace as needed.
(18)= Adjust valve lash. Incorrect valve clearance
will result in increased engine noise and reduced engine
output.(19)= With the engine off and below normal operating
temperature, check to see that the thermostatically
controlled engine cooling fan can be rotated by hand on
viscous-operated drives. Replace as needed.
(20)= Check shields and underhood insulation for
damage or looseness. Adjust or replace as needed.
(21)= Inspect parking brake drum and linings for wear
or cracks and check linkage and adjustment.
(22)= Wheel bearing service:
•Grease type — Clean, inspect, and lubricate with
the proper wheel bearing grease at designated
intervals or when hubs are removed. SeePart C:
Recommended Fluids and Lubricants on page 6-32.
•Oil-filled type — Some wheel bearings are
lubricated by rear axle lubricant. When you have
oil-filled hubs, use lubricant identical to that used in
your rear axle. Lubricant change intervals are
the same for front and rear axles. However, you
must maintain the proper oil level between change
intervals. SeeFront Wheel Bearings with Oil-Filled
Hubs on page 5-69andPart C: Recommended
Fluids and Lubricants on page 6-32.
(23)= Check the air intake system installation to see
that gaskets are seated properly and all hose
connections, fasteners, and other components are tight.
Tighten connections and fasteners or replace parts
as required.
6-24
Part C: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number, or specification may be obtained from
your dealer.
Usage Fluid/Lubricant
Engine Oil
(Gasoline
Engine)Engine oil which meets GM
Standard GM6094M and displays
the American Petroleum Institute
Certified for Gasoline Engines
starburst symbol. GM Goodwrench
®
oil meets all the requirements for
your vehicle. To determine the
proper viscosity for your vehicle’s
engine, see “Engine Oil” in
the Index.
Engine Oil
(DURAMAX
®
Diesel Engine)Engine oil with the letters CI-4 or
CH-4 is best for your vehicle. The
CI-4 or CH-4 designation may
appear either alone or in
combination with other API
designations, such as API CI-4/SL.
These letters show American
Petroleum Institute levels of quality.
To determine the preferred viscosity
for your vehicle’s diesel engine, see
“Engine Oil” in the Index.
Engine Oil
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine oil
recommendations.
Usage Fluid/Lubricant
Engine Coolant
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine
coolant recommendations.
Engine Coolant
(Gasoline
Engine &
DURAMAX
®
Diesel)50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. See “Engine Coolant” in
the Index.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
Washer SolventGM Optikleen
®Washer Solvent.
Clutch Bearing
LubricantClutch Bearing Lubricant
(GM Part No. 12378484 or
equivalent NLGI #3 consistency).
Exhaust Brake
Ball Joint Cap
LubricantHigh-Temperature Grease
(GM Part No. U.S. 1051344, in
Canada 903037) or NLGI #3
consistency.
Power Steering
SystemDEXRON
®-III Automatic
Transmission Fluid. Look for
“Approved for the H-Specification”
on the label.
Manual
Transmission
(Except ZF
6-Speed)Synthetic Manual Transmission Fluid
(GM Part No. U.S. 12345724, in
Canada 10953510).
6-32
Driving (cont.)
Drunken....................................................... 4-2
Freeway.....................................................4-22
Hill and Mountain Roads..............................4-24
In Rain and on Wet Roads...........................4-18
Rocking Your Vehicle to Get it Out.................4-30
Tow Hooks.................................................4-31
Winter........................................................4-26
Dual Tire Operation.........................................5-72
E
Electrical System
Add-On Equipment......................................5-88
Fuses and Circuit Breakers...........................5-89
Fusible Links..............................................5-89
Headlamp Wiring.........................................5-88
Instrument Panel Fuse Block.........................5-89
Power Windows and Other Power Options......5-89
Underhood Fuse Block.................................5-92
Windshield Wiper Fuses...............................5-88
Engine
Air Cleaner/Filter.........................................5-33
Alarm and Automatic Shutdown.....................2-18
Battery.......................................................5-55
Change Engine Oil Light...............................3-38
Check and Service Engine Soon Light............3-36Engine (cont.)
Checks Before Operating..............................2-22
Coolant..............................................5-36, 5-38
Coolant Heater............................................2-24
Coolant Temperature Gage...........................3-35
Diesel Engine Exhaust Brake........................2-25
Exhaust.....................................................2-43
Exhaust Restrictor.......................................2-21
Fan Noise..................................................5-45
High Idle System.........................................2-19
Oil .....................................................5-22, 5-26
Oil Life System...........................5-29, 5-31, 5-32
Overheating................................................5-38
Overspeed Warning Light..............................3-39
Reduced Power Light...................................3-41
Shutdown Warning Light...............................3-39
Speed Limiter.............................................3-26
Starter Over-Crank Protection........................2-12
Starting Your Diesel.....................................2-14
Starting Your Gasoline..................................2-12
Entry Lighting.................................................3-17
Event Data Recorders (EDR)............................. 7-6
Exhaust Brake Indicator Light...........................3-40
Exhaust Restrictor...........................................2-21
Extender, Safety Belt.......................................1-26
Exterior Lamps...............................................3-14
5
G
Gage
Air Pressure...............................................3-44
Check Gages Warning Light..........................3-42
Engine Coolant Temperature.........................3-35
Filter Minder...............................................3-43
Fuel..........................................................3-42
Hourmeter..................................................3-44
Oil Pressure...............................................3-37
Speedometer..............................................3-26
Tachometer.................................................3-26
Transmission Temperature.............................3-39
Voltmeter Gage...........................................3-30
Gasoline
Octane........................................................ 5-6
Specifications............................................... 5-6
Gasoline Engine, Starting.................................2-12
GM Mobility Reimbursement Program.................. 7-5
H
Hazard Warning Flashers................................... 3-6
Headlamp Wiring............................................5-88
Headlamps
Bulb Replacement.......................................5-65
Daytime Running Lamps...............................3-15
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-15Heater...........................................................3-20
High Idle System............................................2-19
Highbeam On Light.........................................3-41
Highway Hypnosis...........................................4-23
Hill and Mountain Roads..................................4-24
Hood
Checking Things Under................................5-20
Latches......................................................5-20
Horn............................................................... 3-6
Hourmeter Gage.............................................3-44
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-14
Hydraulic Brake Systems................................... 4-6
Hydraulic Brakes.............................................2-38
I
Ignition Positions.............................................2-12
Infants and Young Children, Restraints...............1-30
Inflation -- Tire Pressure..................................5-71
Instrument Panel
Overview..................................................... 3-4
Switchbank.................................................3-18
Instrument Panel (I/P)
Brightness..................................................3-16
Cluster.......................................................3-25
7