Item Number Item Remarks
4 Pivot Points and Hinges Apply chassis lubricant.
5 Pivot Points and Hinges Apply chassis lubricant.
6 Slack Adjuster** One fitting.
7Brake Cam Roller Pins at interface of pin
and shoe**Apply engine oil.
8 Front Steering KnucklesOne fitting each side, lower bushing.
(Hand-operated grease gun only.) Hand-pack
upper bearing.
9 Front Wheel Bearings Hand-pack or lubricate.
10 Steering Tie Rod Ends One fitting each end.
11 Spring Slip Pads* (Multi-Leaf Only) Apply chassis lubricant.
12 Clutch Release Bearing* Cup or fitting.
13 Battery Terminal (except “ST” type) Keep coated with petroleum jelly.
14 Transmission Fill to level of filler plug.
15 Propshaft U-JointsLubricate with GM Part No. 1051344 Wheel
Bearing Lubricant.
16 Parking Brake Clevis Pin$ Apply chassis lubricant.
17 Parking Brake Lever Pivot*, $ Apply chassis lubricant.
18Clutch Release Cross Shaft, Master
Cylinder$Apply chassis lubricant, fill to 1/4 inch (6 mm)
below opening.
19 Release Bearing, Clutch Cross Shaft Two fittings, apply chassis lubricant.
20 Clutch Release Fork Two fittings.
* Applies to some vehicles.
** Applies to air brakes only.
$ Applies to hydraulic brakes only.
303
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 and Isuzu 6H diesel engine vehicles have a
computer that lets you know when to change the
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 276orEngine
Oil Life System (DURAMAX
®Diesel) on page 278
orEngine Oil Life System (Caterpillar®Diesel
Engine) on page 279.
The “Footnotes” at the end of this Maintenance
Schedule further explain maintenance services.
SeeService Publications Ordering Information
on page 415.
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)
363
❑Clean air brake application valve (or every
3 months, or every 300 hours, whichever
occurs first). Lubricate linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)
100,000 Miles (160 000 km)
❑Diesel Only: Inspect engine drive belt;
replace as necessary.
❑Gasoline Engine Only (Vehicles with
GVW of 16,000 lbs or less): Spark plug
service.(2) (25)
❑Change power steering fluid (or every
36 months, whichever occurs first).(12)
❑Replace power steering reservoir filter element
(or every 24 months, whichever occurs first).
❑Wheel bearing (oil type) service (and whenever
hubs are removed).(22) (36)
❑Except four-wheel drive: Front axle service.(31)
❑Four-wheel drive only: Front axle service.(30)
❑Four-wheel drive only: Transfer case
service.(30)
❑Rear axle service — Eaton
®, Rockwell®,
Spicer®axles (or every 12 months, whichever
occurs first).(30)❑Exhaust brake service, if equipped. Check for
excessive spindle free play and smooth
operation. Lubricate ball joint cap.
❑Inspect air compressor discharge port (or every
6 months or every 1,800 hours, whichever
occurs first).
❑Manual transmission (ZF 6-speed only) fluid
replacement (or every 48 months, whichever
occurs first).
❑Trailer brake hand control valve service (or every
12 months, or every 3,600 hours, whichever
occurs first).(35)
120,000 Miles (192 000 km)
❑C600, C700, and C800 Gasoline Engines Only:
Replace engine drive belts.
❑C400 and C500 Gasoline Engines Only: Engine
drive belts service (or every 12 months,
whichever occurs first).(17)
150,000 Miles (240 000 km)
❑Cooling system service (or every 60 months
since last service, whichever occurs
first).(2) (29)
❑Diesel Engine Only: Inspect engine drive belt;
replace as necessary.
382
(2)= An Emission Control Service.
(3)= A Noise Emission Control Device.
(4)= Applies to vehicles sold in the United States
and is recommended for vehicles sold in Canada.
(5)= Check fluid level in brake master cylinder,
power steering pump, front and rear axles,
transmission, and hydraulic spring parking brake
pump (if equipped). A low fluid level in the
brake master cylinder can indicate worn brake
linings and should be checked accordingly.
(6)= 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 caliper assemblies.
Check brake pedal for excessive free play or
travel (or every 6 months, whichever occurs first)
and have serviced if needed. Check brakes
more often if driving habits and conditions result
in frequent braking.(7)= This vehicle has the Engine Oil Life System.
This system will show you when to change the
engine oil and filter — usually between 3,000 miles
(5 000 km) and 12,000 miles (20 000 km) since
your last oil change. Under severe conditions,
the indicator may come on before 3,000 miles
(5 000 km). Never drive your 7.8L diesel engine
vehicle more than 12,000 miles (20 000 km),
or 12 months, or 600 engine hours, without an
oil and filter change.
Remember to reset the Engine Oil Life System
whenever the oil is changed. For more information,
seeEngine Oil Life System (Gasoline Engine)
on page 276orEngine Oil Life System
(DURAMAX
®Diesel) on page 278orEngine
Oil Life System (Caterpillar®Diesel Engine)
on page 279.
384
(11)= Chassis Lubrication Service: Lubricate all
grease fittings in front suspension, front axle,
and steering linkage. DO NOT lubricate kingpin
bushings with air pressure equipment; instead,
use a hand grease gun to ensure complete purge
and eliminate sealer cap distortion. Front axle
tie rod ends, both upper and lower kingpin fittings,
and both steering linkage relay rod ends should
be greased with the vehicle loaded on the ground
and wheels turned straight ahead, NOT with
the vehicle on a hoist. Apply kingpin bushing
lubricant to both upper and lower kingpin grease
fittings until new lubricant purges from between
the upper shim pack and thrust bearing. Lubricate
transmission and shift linkage, hood latches
and hood hinges, parking brake lever pivot, clevis
pins and linkage, disc brake caliper rails, clutch
linkage and release bearing (if equipped), bearing
pads, propshaft universal joints, brake camshaft
bracket, slack adjusters, pedal shaft, clutch
cross shaft, clutch pedal springs, and clutch cable
bushing at transmission. Lubricate suspension,
axle, and steering linkage more often when
operating under dusty or muddy conditions and in
excessive off-road use. Frequently power-washed
vehicles will require more frequent lubrication.(12)= Check steering system:
•Look for damaged, loose, or missing parts.
Inspect the steering linkage relay rod and
tie rod ends for looseness or lack of lubricant.
Also look for parts showing signs of wear
or lack of lubrication. Replace parts as
needed. Also check steering gear mounting
bolts, pitman arm nut, gear housing upper
cover and side cover attaching bolts, steering
column mounting bolts and cardan joint
clamp bolts; tighten if necessary. See the
service manual.
•Inspect power steering hoses, tubes, and
fittings for leaks. Hoses and lines must not
be twisted, kinked, or tightly bent. Make sure
clips, clamps, supporting tubes, and hoses
are in place and properly secured.
•Check steering gear for leakage around
pitman shaft and housing. If leakage is evident
(lubricant oozing out, not just oily film), leak
should be corrected immediately.
386
Usage Fluid/Lubricant
Front Wheel
Bearings
(Except Oil
Filled Hubs)Wheel bearing lubricant meeting
requirements of NLGI #2,
Category GC or GC-LB
(GM Part No. U.S. 1051344,
in Canada 993037).
Front Wheel
Bearings with
Oil Filled HubsSAE 75W-90 Synthetic Axle
Lubricant for Medium Duty Trucks
(GM Part No. U.S. 89021675,
in Canada 10953512).
Transfer Case
(Four-Wheel
Drive)Manual Transmission Fluid
(GM Part No. U.S. 88861800,
in Canada 88861801).
Front Axle
(Four-Wheel
Drive)SAE 75W-90 Synthetic Axle
Lubricant for Medium Duty Trucks
(GM Part No. U.S. 89021675,
in Canada 10953512).
Rear Axle and
Rear HubsSAE 75W-90 Synthetic Axle
Lubricant for Medium Duty Trucks
(GM Part No. U.S. 89021675,
in Canada 10953512).Usage Fluid/Lubricant
Rear Axle Shift
Motor LubricantRefrigerant Oil
(GM Part No. U.S. 5416939,
in Canada 10953496).
Propshafts
and SplinesWheel bearing lubricant meeting
requirements of NLGI #2,
Category GC or GC-LB
(GM Part No. U.S. 1051344,
in Canada 993037).
Cab — Door
Hinges and
LatchesMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241,
in Canada 10953474).
Weatherstrip
ConditioningWeatherstrip Lubricant
(GM Part No. U.S. 3634770,
in Canada 10953518) or
Dielectric Silicone Grease
(GM Part No. U.S. 12345579,
in Canada 992887).
Weatherstrip
SqueaksSynthetic Grease with
Teflon, Superlube
(GM Part No. U.S. 12371287,
in Canada 10953437).
399
Flashers, Hazard Warning........................... 142
Flat Tire...................................................... 330
Fluid
Automatic Transmission............................ 282
Manual Transmission................................ 283
Power Steering........................................ 295
Windshield Washer.................................. 296
Four-Wheel Drive...............................119, 312
Front Axle................................................... 313
Front Wheel Bearings with Oil-Filled Hubs ... 319
Fuel............................................................ 251
Additives.................................................. 252
Diesel Engine Fuel................................... 253
Filling a Portable Fuel Container.............. 266
Filling Your Tank...................................... 264
Filter........................................................ 317
Filter Replacement................................... 263
Fuels in Foreign Countries....................... 264
Gage....................................................... 181
Gasoline Octane...................................... 251
Gasoline Specifications............................ 251
Primary Filter and Water Separator.......... 317
Running Out of Fuel................................ 262
Secondary Filter and Water Separator/
Heater.................................................. 318
Very Cold Weather Operation................... 256
Water in Fuel........................................... 256Fuel (cont.)
Water in Warning Light............................ 182
What Fuel to Use.................................... 253
Fuses
Fuses and Circuit Breakers...................... 341
Instrument Panel Fuse Block................... 342
Underhood Fuse Block............................. 344
Windshield Wiper..................................... 341
G
Gage
Air Pressure............................................. 183
Check Gages Warning Light..................... 180
Engine Coolant Temperature.................... 173
Filter Minder............................................ 182
Fuel......................................................... 181
Hourmeter................................................ 183
Oil Pressure............................................. 175
Speedometer........................................... 163
Tachometer.............................................. 163
Transmission Temperature........................ 178
Voltmeter Gage........................................ 168
Gasoline
Octane..................................................... 251
Specifications........................................... 251
Gasoline Engine, Starting.............................. 97
GM Mobility Reimbursement Program.......... 407
422
L
Lamps
Dome....................................................... 153
Exterior.................................................... 150
Marker..................................................... 152
Reading................................................... 154
LATCH System
Child Restraints......................................... 57
Light
Airbag Off................................................ 166
Airbag Readiness..................................... 165
Anti-Lock Brake System Warning............. 172
Brake System Warning............................. 169
Change Engine Oil................................... 176
Charging System..................................... 167
Check Gages Warning............................. 180
Daytime Running Lamps Indicator............ 179
Differential Lock Indicator......................... 178
Engine Overspeed Warning...................... 177
Engine Shutdown Warning....................... 177
Exhaust Brake Indicator........................... 178
Highbeam On.......................................... 179
Low Coolant Warning............................... 173
Low Oil Level........................................... 176
Low Washer Fluid Warning...................... 180
Malfunction Indicator................................ 174Light (cont.)
Range Inhibit Warning Indicator................ 169
Reduced Engine Power............................ 179
Safety Belt Reminder............................... 164
Safety Belt Reminder Tone...................... 164
Service Transmission Warning.................. 168
Trailer Anti-Lock Brake System Warning ... 172
Wait to Start Indicator.............................. 174
Water in Fuel Warning............................. 182
Lighting
Entry........................................................ 154
Loading Your Vehicle................................... 238
Locks
Door.......................................................... 91
Power Door............................................... 92
Loss of Control........................................... 221
Low Coolant Warning Light.......................... 173
Low Washer Fluid Warning Light................. 180
M
Maintenance, Normal Replacement Parts.... 352
Maintenance Schedule
At Each Fuel Fill...................................... 391
At Least Once a Year.............................. 396
At Least Twice a Year.............................. 392
How This Section is Organized................ 360
424