
(24)= Evaporative Control System Service, if equipped:
Check all fuel and vapor lines and hoses for proper
connections and correct routing (or every 24 months,
whichever occurs first). Replace parts as needed.
(25)= Replace spark plugs. Inspect wires for damage.
Check the wire boot and boot heat shield fit at spark
plugs and coil. Replace parts as needed.
(26)= Check the fuel tank, fuel cap and fuel lines for
damage which could cause leakage. Inspect fuel cap for
correct sealing ability and any indications of damage.
Check fuel cap gasket for even filler neck imprint.
Replace parts as needed.
(27)= Check Exhaust Gas Recirculation (EGR) system
as described in the service manual. SeeService
Publications Ordering Information on page 7-10.
(28)= Inspect Electronic Vacuum Regulator Valve
(EVRV) filter for excessive contamination or plugging.
If needed, clean filter with solution of soap and water, let
dry and install.
(29)= Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. SeePart C: Recommended Fluids
and Lubricants on page 6-31for what to use. Inspect
hoses. Clean radiator, condenser, pressure cap, and
neck. Pressure test cooling system and pressure cap.
For Caterpillar
®diesel engines, always refer to the
Caterpillar®Diesel Engine Operation & Maintenance
Manual for coolant recommendations and change
intervals.(30)= Change the lubricant. SeePart C: Recommended
Fluids and Lubricants on page 6-31.
(31)= Front axle service: Re-pack upper kingpin roller
bearing.
(32)= 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.
6-24

•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, service brake chambers, quick release valves,
quick release/double check valve combinations,
parking brake control valve, double check valves,
pressure protection valves, and ether 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.
(33)= Clean and lubricate air brake automatic slack
adjuster. Check pushrod travel and auto adjustment
operation. Have serviced if needed.
(34)= Air brake chamber service: Check operation,
mounting clamps, and air lines and check for leaks.
(35)= Trailer brake hand control valve service: Check
operation; lubricate cam and follower.(36)= 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 5-80.
(37)= Inspect and clean any accumulated dirt, gravel,
or other foreign objects from the valves and valve boots
as needed. Using light oil, lubricate brake pedal to
brake application valve linkage components. Check any
rubber boots for cracks, holes, or deterioration and
replace if necessary.
(38)= Estimated minimum. Actual mileage depends on
fuel and oil consumed.
(39)= If the vehicle has the Isuzu diesel engine and is
used primarily for long trip, highway service, change
the engine oil and filter every 18,000 miles (28 800 km),
or every 12 months, or every 750 hours of engine
operation, whichever occurs first.
(40)= Make sure any 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.
6-25

Automatic Transmission Shift Indicator
Check
Check that the indicator points to the gear chosen.
Steering Check
Be alert for any changes in steering action, abnormal
front tire wear or steering wheel position. An inspection
or service is needed when the steering wheel is
harder to turn or has too much free play, or if there are
strange sounds when turning or parking.
Brake System Check
Be alert to the low air warning light or tone alarm, or
changes in braking action, such as repeated pulling to
one side, unusual sounds when braking or increased
brake pedal travel. Make sure air brake system reservoirs
are drained daily with full system air pressure, and check
system for leaks. Any of these conditions could indicate
the need for brake system inspection and/or service.
Engine Cooling System Service
Inspect the hoses and have them replaced if they are
cracked, swollen, or deteriorated. Inspect all pipes,
fittings, and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser. To
help ensure proper operation, a pressure test of the
cooling system and pressure cap is recommended at
least once a year.
Exhaust System Inspection
Be alert for any changes in the sound of the exhaust
system or any smell of fumes. These are signs the
system may be leaking. Have it checked and/or repaired
at once. SeeEngine Exhaust on page 2-45and
Running the Vehicle While Parked on page 2-50.
Check to be sure that mud or dirt is not caked on the
exhaust system, especially in the area of the diesel
particulate filter and tailpipe. Clean the area as needed.
SeeDiesel Particulate Filter on page 2-46.
At high mileages, the DPF becomes loaded with ash.
This is normal. When the amount of ash loading is high,
see your dealer/retailer for DPF cleaning or replacement.
Windshield Wipers and Washers
Check
Check operation and condition of the wiper blades.
Check the flow of the washer spray.
Defroster Check
Move the control to the defrost symbol and the fan to HI
or the high symbol. Then check the airflow from the
ducts at the inside base of the windshield.
6-28

Engine (cont.)
Overheating................................................5-48
Overspeed Warning Light..............................3-40
Reduced Power Light...................................3-42
Shutdown Warning Light...............................3-40
Speed Limiter.............................................3-25
Starter Over-Crank Protection........................2-12
Starting Diesel............................................2-14
Starting the Gasoline...................................2-12
Entry Lighting.................................................3-17
Event Data Recorders.....................................7-12
Exhaust Brake Indicator Light...........................3-41
Exhaust Restrictor...........................................2-22
Extender, Safety Belt.......................................1-28
Exterior Lamps...............................................3-14
F
Filter
Engine Air Cleaner......................................5-38
Filter Minder Gage..........................................3-46
Finish Damage...............................................5-93
Fixed Mast Antenna........................................3-58
Flashers, Hazard Warning.................................. 3-6
Flat Tire........................................................5-85
Fluid
Automatic Transmission................................5-42
Power Steering...........................................5-49
Windshield Washer......................................5-50
Four-Wheel Drive....................................2-30, 5-68Front Axle......................................................5-69
Front Wheel Bearings with
Oil-Filled Hubs............................................5-75
Fuel............................................................... 5-6
Additives...................................................... 5-7
Change Filter Warning Light..........................3-45
Diesel Engine Fuel........................................ 5-8
Driving for Better Economy............................. 4-2
Filling a Portable Fuel Container....................5-22
Filling the Tank...........................................5-20
Filter..........................................................5-72
Filter Replacement.......................................5-18
Fuels in Foreign Countries............................5-19
Gage .........................................................3-44
Gasoline Octane........................................... 5-6
Gasoline Specifications.................................. 5-7
Primary Filter and Water Separator................5-73
Running Out of Fuel....................................5-17
Secondary Filter and Water
Separator/Heater......................................5-74
Very Cold Weather Operation........................5-11
Water in Fuel..............................................5-11
Water in Warning Light.................................3-45
What Fuel to Use.......................................... 5-8
Fuses
Fuses and Circuit Breakers...........................5-96
Instrument Panel Fuse Block.........................5-96
Underhood Fuse Block.................................5-99
Windshield Wiper.........................................5-95
5

M
Maintenance, Replacement Parts.....................5-108
Maintenance Schedule
At Each Fuel Fill.........................................6-26
At Least Once a Year..................................6-30
At Least Twice a Year..................................6-27
How This Section is Organized....................... 6-3
Introduction.................................................. 6-2
Maintenance Requirements............................. 6-2
Part A - Scheduled Maintenance Services......... 6-4
Part B - Owner Checks and Services.............6-26
PartC-Recommended Fluids and
Lubricants...............................................6-31
PartD-Maintenance Record........................6-33
Scheduled Maintenance................................. 6-5
Scheduled Maintenance Supplements............... 6-4
Using.......................................................... 6-4
Your Vehicle and the Environment................... 6-2
Malfunction Indicator Lamp...............................3-36
Manual Transmission
Fluid..........................................................5-42
Operation...................................................2-28
Manual Windows.............................................. 2-9
Marker Lamps................................................3-16
Mirrors
Manual Rearview Mirror................................2-51
Outside Convex Mirrors................................2-52
Outside Heated Mirrors................................2-52
Outside Manual Mirrors................................2-51
Outside Power Mirrors..................................2-51
N
Navigation System, Privacy..............................7-13
New Vehicle Break-In......................................2-10
Noise Control System, Tampering......................5-70
O
Odometer......................................................3-25
Odometer, Trip...............................................3-25
Off-Road Recovery..........................................4-11
Oil
Change Engine Oil Light...............................3-39
Engine...............................5-24, 5-27, 5-28, 5-32
Low Oil Level Light......................................3-39
Pressure Gage............................................3-38
Oil, Engine Oil Life System..............5-35, 5-36, 5-38
Older Children, Restraints................................1-28
OnStar, Privacy..............................................7-13
Other Service Items
Front Wheel Bearings with
Oil-Filled Hubs.........................................5-75
Primary Fuel Filter and Water Separator.........5-73
Secondary Fuel Filter and Water
Separator/Heater......................................5-74
Outlet Adjustment............................................3-22
Outlets
Accessory Power.........................................3-19
8

Starting the Gasoline Engine............................2-12
Steering.......................................................... 4-9
Steering Wheel, Tilt Wheel................................. 3-6
Storage Areas................................................2-53
Center Console Storage Area........................2-53
Stuck in Sand, Mud, Ice, or Snow.....................4-19
Sun Visors...................................................... 2-9
Suspension, Air..............................................2-44
Switchbanks, Instrument Panel..........................3-18
T
Tachometer....................................................3-25
Theft-Deterrent, Radio.....................................3-57
Tilt Wheel........................................................ 3-6
Time, Setting..................................................3-48
Tires.............................................................5-76
Aluminum or Chrome-Plated Wheels,
Cleaning.................................................5-92
Buying New Tires........................................5-79
Cleaning....................................................5-92
Dual Tire Operation.....................................5-78
If a Tire Goes Flat.......................................5-85
Inflation - Tire Pressure................................5-77
Tightening the Wheel Nuts............................5-80Tires (cont.)
Wheel Alignment and Tire Balance.................5-80
Wheel Loading............................................5-78
Wheel Replacement.....................................5-84
When It Is Time for New Tires......................5-78
Tow Hooks.....................................................4-20
Towing
Your Vehicle...............................................4-23
Traction
Control System (TCS).................................... 4-8
Trailer
Connections................................................4-25
Trailer Brake Hand Control Valve........................ 4-6
Transmission
Fluid, Automatic...........................................5-42
Fluid, Manual..............................................5-42
Service Warning Light..................................3-30
Temperature Gage.......................................3-40
Transmission Operation, Automatic....................2-27
Transmission Operation, Manual........................2-28
Trip Odometer................................................3-25
Turn and Lane-Change Signals.......................... 3-7
Turn Signal/Multifunction Lever........................... 3-7
Two-Speed Rear Axle......................................2-36
11