
(11)= Inspect rear axle air shift motor for fluid leaks.
Remove plug to check fluid level. Inspect air lines
and hoses for proper hook-up, binding, leaks, etc.
Inspect at 1,000 miles (1 600 km) and 22,500 miles
(36 000 km) and then every 22,500 miles (36 000 km)
thereafter.
(12)= 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 steeringlinkage more often when operating under dusty or
muddy conditions and in excessive off-road use.
Frequently power-washed vehicles will require more
frequent lubrication.
(13)= 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 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.
6-20

(14)= Check front and rear suspension. Look for
damaged, loose or missing parts or parts showing signs
of wear or lack of lubrication. Replace parts as
needed.
(15)= Adjust tire pressures as indicated on the GVW
Rating label for optimum tire life. SeeTires on page 5-68
for further details. Check tires for excessive or
abnormal wear or damage. Also check for damaged
wheels. Replace wheels and/or tires as needed.
(16)= 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.
(17)= 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.(18)= Check all gasoline engine drive belts for cracks,
fraying and wear. Replace as needed.
(20)= 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.
(21)= Check shields and underhood insulation for
damage or looseness. Adjust or replace as needed.
23)= 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 6-29.
•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 oil
level at the OIL LEVEL mark between change
intervals. SeePart C: Recommended Fluids and
Lubricants on page 6-29.
6-21

(39)= Air brake service:
•Inspect brake lines and hoses for proper hook-up,
binding, leaks, cracks, chafing, etc. Inspect drum
brake linings for wear or cracks. Inspect other brake
parts at each wheel, including drums and wheel
speed sensor wiring. 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. Replace air
dryer cartridge only if excessive oil or moisture
is present. A small amount of oil in the system is
normal and should not be considered as a reason to
replace the cartridge.
•Test air lines for leaks; tighten as needed. Replace
compressor filter.
•Inspect air parking brake chamber for leaks and
damage. Inspect lines and hoses for leaks,
cracks, chafing, etc. Also check all attachments for
tightness, wear or damage. Note: The spring
brake section of the rear brake diaphragms are
non-serviceable.
•Replace the air compressor filter element, mounted
on the air compressor. For remote air compressor
intake service, refer to engine air cleaner filter
replacement.
•Remove, disassemble, clean and inspect the safety
valve, standard brake chambers, quick release
valves, quick release/double check valve
combinations, parking brake control valve, double
check valves, pressure protection valves and
alcohol injector (if equipped).
•Remove, disassemble and clean the application
valve; replace parts showing wear.
•Remove, disassemble, clean and inspect the spring
brake control valve; replace rubber parts.
(40)= Clean and lubricate air brake automatic slack
adjuster. Check pushrod travel and auto adjustment
operation. Have serviced if needed.
(41)= Air brake chamber service: Check operation,
mounting, clamps and air lines and check for leaks.
(42)= Trailer brake hand control valve service: Check
operation; lubricate cam and follower.
(46)= Tighten the wheel stud nuts to the specified
torque values at 100 miles (160 km). Thereafter, tighten
them 1,000 miles (1 600 km) after each time the
wheel is removed. SeeTightening the Wheel Nuts on
page 5-71.
6-23

G
Gage
Air Pressure...............................................3-44
Check Gages Warning Light..........................3-42
Engine Coolant Temperature.........................3-35
Filter Minder...............................................3-44
Fuel..........................................................3-42
Hourmeter..................................................3-45
Oil Pressure...............................................3-37
Speedometer..............................................3-25
Tachometer.................................................3-26
Transmission Temperature.............................3-40
Voltmeter Gage...........................................3-30
Gasoline
Octane........................................................ 5-6
Specifications............................................... 5-6
Gasoline Engine, Starting.................................2-12
Gasoline Engine Warm-Up...............................2-14
Glass, Mirrors, Lamps and/or Reflectors
Condition Check..........................................6-27
H
Hazard Warning Flashers................................... 3-5
Headlamp High/Low-Beam Changer.................... 3-8
Headlamp Wiring............................................5-86Headlamps On Reminder.................................3-13
Heavy-Duty Trailer Wiring Package....................4-35
Height Adjustment............................................. 1-6
High Idle System (Caterpillar
®Diesel and
Gasoline Engines).......................................2-16
Highway Hypnosis...........................................4-23
Hill and Mountain Roads..................................4-23
Hood
Checking Things Under................................5-18
Latches......................................................5-19
Hood Latches Check.......................................6-28
Horn............................................................... 3-6
Hourmeter Gage.............................................3-45
How to Add Coolant to the Coolant
Surge Tank.................................................5-39
How to Add Fluid............................................5-32
How to Check................................................5-69
How to Check and What to Use...............5-31, 5-32
How to Check Fluid........................................5-61
How to Check Lubricant...................................5-61
How To Check Power Steering Fluid..................5-43
How to Inspect the Engine Air Cleaner/Filter.......5-30
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-13
Hydraulic Brake System
Warning Lights............................................3-32
Hydraulic Brake Systems................................... 4-6
Hydraulic Brakes.............................................2-33
Hydroplaning..................................................4-20
7

Matching Transmitter(s) to Your Vehicle............... 2-5
Mexico, Central America and Caribbean
Islands/Countries (Except Puerto Rico and
U.S. Virgin Islands)....................................... 7-4
Mirrors
Manual Rearview Mirror................................2-39
Outside Convex Mirrors................................2-40
Outside Heated Mirrors................................2-41
Outside Manual Mirrors................................2-39
Outside Power Mirrors..................................2-40
Mirrors and Sun Visors Check..........................6-27
Model Reference................................................ vi
Moisture Ejector..............................................5-50
MyGMLink.com................................................ 7-3
N
New Vehicle Break-In......................................2-11
Noise Control System, Tampering......................5-62
Normal Maintenance Replacement Parts...........5-100
O
Odometer......................................................3-25
Off-Road Recovery..........................................4-14Oil
Change Engine Oil Light...............................3-39
Engine...............................................5-20, 5-25
Low Oil Level Light......................................3-38
Pressure Gage............................................3-37
Older Children, Restraints................................1-27
Online Owner Center........................................ 7-3
Other Service Items
Air Conditioning System...............................5-67
Automatic Ether Injection System...................5-66
Front Wheel Bearings with Oil-Filled Hubs.......5-67
Fuel Filter...................................................5-64
Primary Fuel Filter and Water Separator.........5-65
Secondary Fuel Filter and Water Separator/
Heater....................................................5-66
Other Warning Devices...................................... 3-6
Outlet Adjustment............................................3-22
Outside
Convex Mirrors............................................2-40
Heated Mirrors............................................2-41
Manual Mirrors............................................2-39
Power Mirrors.............................................2-40
Overdrive Defeat.............................................2-29
Overspeed Warning Light.................................3-39
Owners, Canadian............................................... ii
Owner’s Information.......................................... 7-8
10