
❑Gasoline Engine: Inspect engine air cleaner filter.
If necessary, replace the filter. If vehicle is driven in
dusty/dirty conditions, inspect filter at every engine oil
change. SeeEngine Air Cleaner/Filter on page 5-38
for more information.
❑Diesel Engine: Inspect engine air cleaner filter change
indicator. If necessary, replace the filter. If vehicle is
driven in dusty/dirty conditions, inspect filter change
indicator at every engine oil change. SeeEngine Air
Cleaner/Filter on page 5-38for more information.
❑Diesel Only: Replace fuel filter (or every 750 hours of
engine operation, whichever occurs first).
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Gasoline Engine Only: Replace fuel filter(s) (or every
12 months, whichever occurs first).(2)
❑Inspect door hinge pins and bushings and replace as
necessary.
❑Check restraint system.(40)
❑Steering system service.(12)
❑Front and rear suspension service.(13)
❑Spring-to-axle U-bolts and shackle bolts service.(15)
❑Exhaust system service (or every 6 months, whichever
occurs first).(2) (3) (16)
❑Wheel bearing (grease type) service (and whenever
hubs are removed).(22) (36)❑Wheels and tires service.(14)
❑Isuzu Diesel Engine Only: Adjust valve lash (or every
2,625 hours of engine operation, whichever occurs
first).(18)
❑Hydraulic brake service (or every 6 months, whichever
occurs first).(6) (36)
❑Parking brake service (or every 6 months, whichever
occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).
❑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)
❑Air compressor dry element pleated paper air strainer
service (or every 2 months, or every 800 hours,
whichever occurs first).
❑C600, C700, and C800 Gasoline Engines Only:
Engine drive belts service (or every 12 months,
whichever occurs first).(17)
6-13

72,000 Miles (115 000 km)
❑Lubricate U-joints (or every 6 months, whichever
occurs first).
75,000 Miles (120 000 km)
❑Gasoline Engine Only: Check engine oil life system.
If engine oil and filter are changed, reset system. See
“Engine Oil (Gasoline Engine)” in the Index.(2) (8)
❑DURAMAX/Isuzu Diesel Without Engine Oil Life
System Only: Change engine oil and filter (or every
12 months, or every 750 hours of engine operation,
whichever occurs first).(2) (39)
❑DURAMAX/Isuzu Diesel With Engine Oil Life System
Only: Check oil life system. If engine oil and filter are
changed, reset system. See “Engine Oil (DURAMAX/
Isuzu Diesel)” in the Index.(2) (9)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (5)
❑Gasoline Engine: Inspect engine air cleaner filter.
If necessary, replace the filter. If vehicle is driven in
dusty/dirty conditions, inspect filter at every engine oil
change. SeeEngine Air Cleaner/Filter on page 5-38
for more information.❑Diesel Engine: Inspect engine air cleaner filter change
indicator. If necessary, replace the filter. If vehicle is
driven in dusty/dirty conditions, inspect filter change
indicator at every engine oil change. SeeEngine Air
Cleaner/Filter on page 5-38for more information.
❑Diesel Only: Replace fuel filter (or every 750 hours of
engine operation, whichever occurs first).
❑Steering system service.(12)
❑Front and rear suspension service.(13)
❑Spring-to-axle U-bolts and shackle bolts service.(15)
❑Exhaust system service (or every 6 months, whichever
occurs first).(2) (3) (16)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months, whichever
occurs first).(6) (36)
❑Parking brake service (or every 6 months, whichever
occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).
6-15

90,000 Miles (144 000 km)
❑Gasoline Engine Only: Check engine oil life system.
If engine oil and filter are changed, reset system. See
“Engine Oil (Gasoline Engine)” in the Index.(2) (8)
❑DURAMAX/Isuzu Diesel Without Engine Oil Life
System Only: Change engine oil and filter (or every
12 months, or every 750 hours of engine operation,
whichever occurs first).(2) (39)
❑DURAMAX/Isuzu Diesel With Engine Oil Life System
Only: Check oil life system. If engine oil and filter are
changed, reset system. See “Engine Oil (DURAMAX/
Isuzu Diesel)” in the Index.(2) (9)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (5)
❑Gasoline Engine: Replace engine air cleaner filter.
SeeEngine Air Cleaner/Filter on page 5-38for more
information.
❑Diesel Engine: Inspect engine air cleaner filter change
indicator. If necessary, replace the filter. If vehicle is
driven in dusty/dirty conditions, inspect filter change
indicator at every engine oil change. SeeEngine Air
Cleaner/Filter on page 5-38for more information.
❑Diesel Only: Replace fuel filter (or every 750 hours of
engine operation, whichever occurs first).
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)❑Cooling system service. Clean the cooling system filler
cap with clean water, clean the core, pressure test the
cap and the system for proper pressure capability, and
inspect condition of cooling and heater hoses and
clamps. Replace hoses if cracked, swollen, or
damaged.
❑Gasoline Engine Only: Replace fuel filter(s) (or every
12 months, whichever occurs first).(2)
❑Check restraint system.(40)
❑Steering system service.(12)
❑Front and rear suspension service.(13)
❑Spring-to-axle U-bolts and shackle bolts service.(15)
❑Exhaust system service (or every 6 months, whichever
occurs first).(2) (3) (16)
❑Inspect door hinge pins and bushings and replace as
necessary.
❑Wheel bearing (grease type) service (and whenever
hubs are removed).(22) (36)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months, whichever
occurs first).(6) (36)
❑Parking brake service (or every 6 months, whichever
occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
6-17

❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).
❑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)
❑DURAMAX Diesel Only: Diesel Particulate
Filter (DPF) service. Then every 100,000 miles
(160 000 km).(7) (38)
6-19

(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.
(13)= 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.
6-22

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

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