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At Least Twice a Year
Wiper Blade Check
Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. SeeWindshield Wiper Blade Replacement on
page 5-76andWindshield and Wiper Blades on
page 5-98for more information.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. Part C tells you what to use.
Body Lubrication Service
Lubricate all exposed surfaces such as door checks,
door lock bolts, lock strike plates, door hinge bushings,
latches, and dovetail bumper wedges. Where oil holes
are provided, a dripless oil can be used. The seat
adjusters, seat track, door weatherstrips, and rubber cap
bumpers should also be lubricated. Part C tells you what
to use. More frequent lubrication may be required when
exposed to a corrosive environment.
Parking Brake Check
Park on a fairly steep hill and hold the vehicle with the
parking brake only. This checks holding ability. See
Parking Brake (With Hydraulic Brakes) on page 2-38or
Parking Brake (With Air Brakes) on page 2-41.
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brakes.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. On automatic transmission vehicles, try to start the
engine in each gear. The starter should work only
in PARK (P) or NEUTRAL (N). If the starter works in
any other position, your vehicle needs service. On
manual transmission vehicles, the starter should
work only when the clutch pedal is all the way down.
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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 (Diesel Engine) 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.
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Underbody Inspection
Corrosive materials used for ice, snow removal, and
dust control can collect on the underbody. If these
materials are not removed, accelerated corrosion (rust)
can occur on underbody parts such as fuel lines, frame,
floor pan, and exhaust system. At least every spring,
flush these materials from the underbody with plain water.
Take care to clean well any areas where mud and other
debris can collect. Sediment packed in closed areas of
the frame should be loosened before being flushed.
Engine Cover Check
Check that the cab’s engine cover and seal, if the
vehicle has one, are not torn or damaged. Be sure that
the cover is clamped down firmly to the floor.
At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part C.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
Tractor Protection (Breakaway) Valve
Check
On air brake models, remove, disassemble, clean, and
inspect the tractor protection (breakaway) valve.
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Part D: Maintenance Record
After the scheduled services are performed, record the date, odometer reading and who performed the service, and
any additional information from “Owner Checks and Services” on the following record pages. Also, you should
retain all maintenance receipts.
DateMiles/km Or
HoursServiced By Maintenance Record
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DateMiles/km Or
HoursServiced By Maintenance Record
6-34
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DateMiles/km Or
HoursServiced By Maintenance Record
6-35
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DateMiles/km Or
HoursServiced By Maintenance Record
6-36
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Customer Assistance and Information...............7-2
Customer Satisfaction Procedure......................7-2
Customer Assistance for Text
Telephone (TTY) Users................................7-3
Customer Assistance Offices............................7-4
GM Mobility Reimbursement Program................7-5
Roadside Assistance Program..........................7-5
Collision Damage Repair.................................7-6
Reporting Safety Defects..................................7-9
Reporting Safety Defects to the United
States Government......................................7-9
Reporting Safety Defects to the Canadian
Government...............................................7-9Reporting Safety Defects to
General Motors...........................................7-9
Service Publications Ordering Information.........7-10
Vehicle Data Recording and Privacy................7-11
Vehicle Data Recording and Privacy
(Isuzu 7.8L L6 Engine)...............................7-11
Event Data Recorders
(Isuzu 7.8L L6 Engine)...............................7-11
OnStar
®(Isuzu 7.8L L6 Engine)......................7-12
Navigation System
(Isuzu 7.8L L6 Engine)...............................7-12
Radio Frequency Identification (RFID)
(Isuzu 7.8L L6 Engine)...............................7-12
Section 7 Customer Assistance Information
7-1