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.
6-28
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.
6-30
Part C: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number, or specification can be obtained from your
dealer/retailer.
Usage Fluid/Lubricant
Engine Oil
(Gasoline
Engine)Engine oil which meets
GM Standard GM6094M and
displays the American Petroleum
Institute (API) Certified for Gasoline
Engines starburst symbol. To
determine the proper viscosity for
your vehicle’s engine, see “Engine
Oil” in the Index.
Engine Oil
(DURAMAX
®/
Isuzu Diesel
Engines)Engine oils with the letters CJ-4 are
required for your vehicle. The CJ-4
designation can appear either alone
or in combination with other
American Petroleum Institute (API)
designations, such as API CJ-4/SL.
These letters show API levels of
quality. To determine the preferred
viscosity for your vehicle’s diesel
engine, see “Engine Oil” in the Index.
Engine Oil
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine oil
recommendations.
Usage Fluid/Lubricant
Engine Coolant
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine
coolant recommendations.
Engine Coolant
(Gasoline
Engine &
DURAMAX
®/
Isuzu Diesel
Engines)50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant
(Caterpillar®Diesel Engines) on
page 5-44orEngine Coolant
(Gas and DURAMAX
®/Isuzu 7.8L
L6 Engines) on page 5-44.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
Washer SolventOptikleen
®Washer Solvent.
Clutch Bearing
LubricantClutch Bearing Lubricant
(GM Part No. 12378484 or
equivalent NLGI #3 consistency).
Exhaust Brake
Ball Joint Cap
LubricantHigh-Temperature Grease
(GM Part No. U.S. 1051344, in
Canada 903037) or NLGI #3
consistency.
Power Steering
SystemDEXRON
®-VI Automatic
Transmission Fluid.
Manual
TransmissionSynthetic Manual Transmission Fluid
(GM Part No. U.S. 88861952, in
Canada 88861953).
6-31
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
GM Mobility Reimbursement
Program
This program, available to qualified applicants, can
reimburse you up to $1,000 of the cost of eligible
aftermarket adaptive equipment required for your vehicle,
such as hand controls or a wheelchair/scooter lift.
The offer is available for a very limited period of time
from the date of vehicle purchase/lease. For more
details, or to determine your vehicle’s eligibility, visit
gmmobility.com or call the GM Mobility Assistance
Center at 1-800-323-9935. Text telephone (TTY) users,
call 1-800-833-9935.
General Motors of Canada also has a Mobility Program.
Call 1-800-GM-DRIVE (463-7483) for details. TTY
users call 1-800-263-3830.
Roadside Assistance Program
GM Medium Duty truck’s Roadside Assistance provides
stranded owner/operators with towing service for
disabled GM Medium Duty trucks, during the base
and/or engine warranty period, to the nearest authorized
GM Medium Duty dealer. This service combines the
efforts of trained telephone representatives with a
network of GM Medium Duty truck services.
Call GM Medium Duty truck’s Roadside Assistance at
1-800-862-4389 to reach a qualified representative who
can assist you in arranging a tow to the nearest GM
Medium Duty truck dealer when your vehicle is disabled.
We also provide dealer information at no charge,
such as location of the nearest authorized GM Medium
Duty truck dealer and their hours of operation.
Our Roadside Assistance is available 24 hours a day,
7 days a week, 365 days a year which includes
weekends and holidays. Should you have questions
about GM Medium Duty truck Roadside Assistance, call
the GM Medium Duty Roadside Assistance Center or
contact your dealer.
Canadian Roadside Assistance
Whenever a Medium Duty truck owned and operated in
Canada becomes disabled, the owner/operator should
contact the Canadian Roadside Assistance Center
at 1-800-268-6800 for assistance.
7-5
Service Publications Ordering
Information
Service Manuals
Service Manuals have the diagnosis and repair
information on engines, transmission, axle suspension,
brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins’ give additional technical service
information needed to knowledgeably service
General Motors cars and trucks. Each bulletin contains
instructions to assist in the diagnosis and service of
your vehicle.
Owner Information
Owner publications are written specifically for owners
and intended to provide basic operational information
about the vehicle. The owner manual includes the
Maintenance Schedule for all models.
In-Portfolio: Includes a Portfolio, Owner Manual, and
Warranty Booklet.
RETAIL SELL PRICE: $35.00 (U.S.) plus processing fee
Without Portfolio: Owner Manual only.
RETAIL SELL PRICE: $25.00 (U.S.) plus processing fee
Current and Past Model Order Forms
Technical Service Bulletins and Manuals are available
for current and past model GM vehicles. To request
an order form, specify year and model name of
the vehicle.
ORDER TOLL FREE: 1-800-551-4123
Monday-Friday 8:00 AM - 6:00 PM
Eastern Time
For Credit Card Orders Only
(VISA-MasterCard-Discover), visit Helm, Inc. on the
World Wide Web at: www.helminc.com
Or you can write to:
Helm, Incorporated
P.O. Box 07130
Detroit, MI 48207
Prices are subject to change without notice and without
incurring obligation. Allow ample time for delivery.
Note to Canadian Customers: All listed prices are
quoted in U.S. funds. Canadian residents are to make
checks payable in U.S. funds.
7-10
Vehicle Data Recording and
Privacy
Vehicle Data Recording and Privacy
(Isuzu 7.8L L6 Engine)
Your GM vehicle has a number of sophisticated
computers that record information about the vehicle’s
performance and how it is driven. For example,
your vehicle uses computer modules to monitor and
control engine and transmission performance, to monitor
the conditions for airbag deployment and deploy
airbags in a crash and, if so equipped, to provide
antilock braking to help the driver control the vehicle.
These modules may store data to help your
dealer/retailer technician service your vehicle. Some
modules may also store data about how you operate the
vehicle, such as rate of fuel consumption or average
speed. These modules may also retain the owner’s
personal preferences, such as radio pre-sets, seat
positions, and temperature settings.
Event Data Recorders
(Isuzu 7.8L L6 Engine)
This vehicle has an Event Data Recorder (EDR). The
main purpose of an EDR is to record, in certain crash or
near crash-like situations, such as an airbag deployment
or hitting a road obstacle, data that will assist in
understanding how a vehicle’s systems performed. The
EDR is designed to record data related to vehicle
dynamics and safety systems for a short period of time,
typically 30 seconds or less. The EDR in this vehicle
is designed to record such data as:
•How various systems in your vehicle were operating
•Whether or not the driver and passenger safety
belts were buckled/fastened
•How far, if at all, the driver was pressing the
accelerator and/or brake pedal
•How fast the vehicle was traveling
This data can help provide a better understanding of the
circumstances in which crashes and injuries occur.
Important:EDR data is recorded by your vehicle only
if a non-trivial crash situation occurs; no data is
recorded by the EDR under normal driving conditions
and no personal data (e.g., name, gender, age,
and crash location) is recorded. However, other parties,
such as law enforcement, could combine the EDR
data with the type of personally identifying data routinely
acquired during a crash investigation.
7-11
To read data recorded by an EDR, special equipment is
required, and access to the vehicle or the EDR is
needed. In addition to the vehicle manufacturer, other
parties, such as law enforcement, that have the special
equipment, can read the information if they have
access to the vehicle or the EDR.
GM will not access this data or share it with others
except: with the consent of the vehicle owner or, if the
vehicle is leased, with the consent of the lessee; in
response to an official request of police or similar
government office; as part of GM’s defense of litigation
through the discovery process; or, as required by
law. Data that GM collects or receives may also be used
for GM research needs or may be made available to
others for research purposes, where a need is shown
and the data is not tied to a specific vehicle or
vehicle owner.
OnStar®(Isuzu 7.8L L6 Engine)
If your vehicle has OnStar and you subscribe to the
OnStar services, please refer to the OnStar Terms and
Conditions for information on data collection and use.
Navigation System
(Isuzu 7.8L L6 Engine)
If your vehicle has a navigation system, use of the
system may result in the storage of destinations,
addresses, telephone numbers, and other trip
information. Refer to the navigation system operating
manual for information on stored data and for deletion
instructions.
Radio Frequency Identi cation
(RFID) (Isuzu 7.8L L6 Engine)
RFID technology is used in some vehicles for functions
such as tire pressure monitoring and ignition system
security, as well as in connection with conveniences
such as key fobs for remote door locking/unlocking and
starting, and in-vehicle transmitters for garage door
openers. RFID technology in GM vehicles does not use
or record personal information or link with any other
GM system containing personal information.
7-12