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{CAUTION:
If wheel studs are damaged, they can break.
If all the studs on a wheel broke, the wheel
could come off and cause a crash. If any stud
is damaged because of a loose-running wheel,
it could be that all of the studs are damaged.
To be sure, replace all studs on the wheel.
If the stud holes in a wheel have become
larger, the wheel could collapse in operation.
Replace any wheel if its stud holes have
become larger or distorted in any way. Inspect
hubs and hub-piloted wheels for damage.
Because of loose running wheels, piloting pad
damage may occur and require replacement of
the entire hub, for proper centering of the
wheels. When replacing studs, hubs, wheel
nuts or wheels, be sure to use GM original
equipment parts.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel
could come off and cause a crash. When
you change a wheel, remove any rust or
dirt from places where the wheel attaches
to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this;
but be sure to use a scraper or wire brush
later, if you need to, to get all the rust or
dirt off.
How Often to Check
Wheel tightness is so important you should have a
technician check nut tightness on all wheels with
a torque wrench after your first 100 miles (160 km), and
then 1,000 miles (1 600 km) after that. Be sure to
repeat this service whenever you have a tire removed or
serviced. SeeScheduled Maintenance on page 6-5for
further information.
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Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, corrosion and rust can develop on the
underbody parts such as fuel lines, frame, floor pan,
and exhaust system even though they have corrosion
protection.
At least every spring, flush these materials from the
underbody with plain water. Clean any areas where mud
and debris can collect. Dirt packed in close areas of
the frame should be loosened before being flushed.
Your dealer/retailer or an underbody car washing system
can do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces on the vehicle. This damage can
take two forms: blotchy, ring-shaped discolorations,
and small, irregular dark spots etched into the paint
surface.
Although no defect in the paint job causes this, we will
repair, at no charge to the owner, the surfaces of new
vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
Vehicle Care/Appearance Materials
Description Usage
Polishing Cloth
Wax-TreatedInterior and exterior
polishing cloth.
Tar and Road Oil
RemoverRemoves tar, road oil and
asphalt.
Chrome Cleaner and
PolishUse on chrome or
stainless steel.
White Sidewall Tire
CleanerRemoves soil and black
marks from whitewalls.
Vinyl Cleaner Cleans vinyl.
Glass CleanerRemoves dirt, grime,
smoke and fingerprints.
Chrome and Wire Wheel
CleanerRemoves dirt and grime
from chrome wheels and
wire wheel covers.
Finish EnhancerRemoves dust,
fingerprints, and surface
contaminants. Spray on
wipe off.
Swirl Remover PolishRemoves swirl marks,
fine scratches and other
light surface
contamination.
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ApplicationCapacities
English Metric
Rear Axle – Two-Speed
19060T (HPL), 22060T (HPH) 38.0 pt 18.0 L
21060T (H15) 38.0 pt 18.0 L
23082T (H25) 44.0 pt 20.8 L
26080T (GJ4) 44.0 pt 20.8 L
Transfer Case (Four-Wheel Drive) 4.0 pt 1.9 L
Transmission Fluid, Automatic
3000 RDS and EVS, and 3500 RDS and EVS with PTO
Provision59.0 pt 28.1 L
3000 RDS and EVS, and 3500 RDS and EVS without PTO
Provision52.0 pt 24.6 L
1000 HS, RDS, MH, PTS and EVS, 2200 HS, RDS, MH,
PTS and EVS, 2500 HS and RDS, and 2300 HS and RDS35.0 pt 16.5 L
Add 2 pints (1 L) when changing spin-on or remote filter.
See the Allison
®Automatic Transmission Operator’s Manual for fluid check and maintenance information.
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Maintenance Replacement Parts
Replacement parts identified by name, part number, or specification can be obtained from your dealer.
Part GM Part Number ACDelco®Part Number
Air Compressor Filter
Haldex compressor (8.1L Engine Only)88915425 A507CF
Engine Air Cleaner/Filter
6.6L V8 (C4/C5 Models) 19152817 A3102C
7.2L L6; Isuzu 6H (C6/C7/C8 Models) with Standard Air
Cleaner88937525 A2031C
7.2L L6; Isuzu 6H (C6/C7/C8 Models) with Heavy Duty Air
Cleaner88937525
1A2031C
8.1L V8 (C4/C5 Models) 88937527 A2032C
8.1L V8 (C6/C7/C8 Models) with Heavy Duty Air Cleaner 88937525 A2031C
8.1L V8 (C6/C7/C8 Models) with Standard Air Cleaner 88937545 A2034C
Engine Oil Filter
6.6L V8 88917036 PF2232
7.2L L6 — 1R-1807††
Isuzu 6H 94392475 —
8.1L V8 25324052 PF454
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Page 325 of 384
Maintenance Schedule......................................6-2
Introduction...................................................6-2
Maintenance Requirements..............................6-2
Your Vehicle and the Environment....................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using the Maintenance Schedule......................6-4
Scheduled Maintenance Supplements................6-4Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-26
At Each Fuel Fill..........................................6-26
At Least Twice a Year...................................6-27
At Least Once a Year...................................6-30
Part C: Recommended Fluids and Lubricants. . . .6-31
Part D: Maintenance Record..........................6-33
Section 6 Maintenance Schedule
6-1
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Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your
dealer/retailer for details.
Maintenance Requirements
Maintenance intervals, checks, inspections and
recommended fluids and lubricants as prescribed in this
manual are necessary to keep your vehicle in good
working condition. Any damage caused by failure to
follow scheduled maintenance may not be covered by
warranty.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. Improper vehicle maintenance can even
affect the quality of the air we breathe. Improper fluid
levels or the wrong tire inflation can increase the level of
emissions from your vehicle. To help protect our
environment, and to keep your vehicle in good condition,
be sure to maintain your vehicle properly.
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How This Section is Organized
This maintenance schedule is divided into four parts:
“Part A: Scheduled Maintenance Services”explains
what to have done and how often. Some of these
services can be complex, so unless you are technically
qualified and have the necessary equipment, you
should let your dealer/retailer do these jobs.
Your dealer/retailer has trained and supported service
people that will perform the work using genuine parts.
{CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you
can be seriously injured. Do your own
maintenance work only if you have the required
know-how and the proper tools and equipment
for the job. If you have any doubt, have a
quali ed technician do the work. SeeDoing
Your Own Service Work on page 5-6.
If you want to purchase service information, seeService
Publications Ordering Information on page 7-10.“Part B: Owner Checks and Services”tells you what
should be checked and when. It also explains what
you can easily do to keep your vehicle in good condition.
“Part C: Recommended Fluids and Lubricants”
lists some recommended products necessary to help
keep your vehicle properly maintained. These products,
or their equivalents, should be used whether you do the
work yourself or have it done.
“Part D: Maintenance Record”is a place for you to
record and keep track of the maintenance performed on
your vehicle. Keep your maintenance receipts. They
may be needed to qualify your vehicle for warranty
repairs.
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Part A: Scheduled Maintenance
Services
In this part are scheduled maintenance services which
are to be performed at the mileage intervals specified.
Using the Maintenance Schedule
We want to help keep your vehicle in good working
condition. But we do not know exactly how you will drive
it. You might drive very short distances only a few times
a week. Or you might drive long distances all the
time in very hot, dusty weather. You might use your
vehicle in making deliveries or in many other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You might need
more frequent checks and replacements. So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your dealer/retailer.
This part tells you the maintenance services you should
have done and when to schedule them.
When you go to your dealer/retailer for your service
needs, you will know that trained and supported service
people will perform the work using genuine parts.The proper fluids and lubricants to use are listed in
Part C. Make sure whoever services your vehicle uses
these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the
vehicle.
This schedule is for vehicles that:
•carry passengers and cargo within recommended
limits. You will find limits on your vehicle’s
Certification or Tire Information label. SeeLoading
Your Vehicle on page 4-21.
•are driven on reasonable road surfaces within legal
driving limits.
•use the recommended fuel. SeeGasoline Octane
on page 5-7for gasoline engine vehicles orWhat
Fuel to Use on page 5-9for diesel engine vehicles.
Scheduled Maintenance
Supplements
If your vehicle has a Caterpillar®diesel engine, your
owner manual is supplemented by the Caterpillar®
Diesel Engine Operation & Maintenance Manual. If your
vehicle has an Allison Transmission®, your owner
manual is supplemented by an Allison Transmission®
Operator’s Manual. Always refer to these manuals
for related maintenance services.
6-4