
Engine Oil
(Caterpillar
®Diesel Engine)
See your Caterpillar®Operation & Maintenance Manual
for information on oil quality and viscosities as well
as the temperature range chart.
Engine Oil (DURAMAX®Diesel)
Checking Engine Oil
It is a good idea to check your engine oil level every
time you get fuel.
The engine oil dipstick is
located in the engine
compartment on the
driver’s side of the vehicle.In order to get an accurate reading, the engine should
be at normal operating temperature, so that the oil
is warm, and the vehicle must be on level ground.
1. If the engine is at normal operating temperature and
the oil is warm, turn off the engine and allow at
least five minutes for the oil to drain back into the
oil pan. If you do not do this, the oil dipstick
might not show the actual level.
If the engine has not been run long enough to bring
it up to normal operating temperature and the oil
is cool, turn off the engine and allow 30 minutes for
the oil to drain back into the oil pan. If you do
not do this, the oil dipstick might not show the
actual level.
2. Pull out the dipstick and clean it with a paper towel
or a cloth, then push it back in all the way.
3. Remove the dipstick again, keeping the tip down,
and check the oil level.
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Engine Oil (Gasoline Engine)
If the low oil light appears
on the instrument cluster, it
means you need to
check your engine oil level
right away. For more
information, seeLow Oil
Level Light on page 3-38.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It is a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.The engine oil dipstick is
located in the engine
compartment on the
driver’s side of the vehicle.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
SeeScheduled Maintenance on page 6-5to determine
when to check your power steering fluid.
How To Check Power Steering Fluid
Check your power steering fluid only when the engine is
warm. If the engine is not warm, you probably will not
get an accurate reading.
If the fluid level is between the MIN (Minimum) and
MAX (Maximum) marks, you have enough. If you need
fluid, add only enough of the proper fluid to bring it
in between the MIN and MAX marks.
If your power steering fluid level is low, this can cause
the brake or service brakes soon warning lights to come
on. In addition, the steering effort and emergency
brake distance could increase.
If either light remains on after you have added power
steering fluid to the proper level, then shut off the engine
for 10 seconds. This should reset the brake warning
lights. If one or both lights stay on, see “Hydraulic Brake
System Warning Lights” underBrake System Warning
Light on page 3-31for more information.
What to Use
To determine what kind of fluid to use, seePart C:
Recommended Fluids and Lubricants on page 6-32.
Notice:When adding power steering uid or
making a complete uid change, always use the
proper uid. Failure to use the proper uid can
cause leaks and damage hoses and seals.
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2. Push the release lever and slide the wiper assembly
toward the driver’s side of the vehicle.
3. Install a new blade by reversing Steps 1 and 2.
Other Service Items
Fuel Filter
Fuel Filter (Gasoline Engines)
The steel fuel filter is located near the engine
compartment on the driver’s side of the vehicle.
See your Maintenance Schedule for recommended
service intervals.
If your vehicle is equipped with the optional Davco
spin-on type filter, it is located on the driver’s side
frame rail.
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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 6-5
for further information.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially if you maintain your tires properly. If air
goes out of a tire, it’s much more likely to leak out
slowly. But if you should ever have a “blow out,” here
are a few tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use
in a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop –– well off the road if possible.
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place and turn on your
hazard warning flashers.
{CAUTION:
Your vehicle, when new, did not include tire
changing equipment or a place to store a tire
in the vehicle. Special tools and procedures
are required if a tire needs to be serviced. If
these tools and procedures are not used, you
or others could be injured or killed while trying
to change or service a truck tire.
Your truck, when new, did not include tire changing
equipment or a place to store a tire in the vehicle. Few
drivers of these vehicles have the necessary equipment
aboard to be able to change a flat tire safely.
5-78

Do not clean your vehicle using the following cleaners
or techniques:
•Never use a knife or any other sharp object to
remove a soil from any interior surface.
•Never use a stiff brush. It can cause damage to
your vehicle’s interior surfaces.
•Never apply heavy pressure or rub aggressively
with a cleaning cloth. Use of heavy pressure
can damage your interior and does not improve the
effectiveness of soil removal.
•Use only mild, neutral-pH soaps. Avoid laundry
detergents or dishwashing soaps with degreasers.
Using too much soap will leave a residue that
leaves streaks and attracts dirt. For liquid cleaners,
about 20 drops per gallon (3.78 L) of water is a
good guide.
•Do not heavily saturate your upholstery
while cleaning.
•Damage to your vehicle’s interior may result from
the use of many organic solvents such as naptha,
alcohol, etc.
Fabric/Carpet
Use a vacuum cleaner with a soft brush attachment
frequently to remove dust and loose dirt. A canister
vacuum with a beater bar in the nozzle may only
be used on floor carpet and carpeted floor mats. For
soils, always try to remove them first with plain water or
club soda. Before cleaning, gently remove as much
of the soil as possible using one of the following
techniques:
•For liquids: gently blot the remaining soil with a
paper towel. Allow the soil to absorb into the
paper towel until no more can be removed.
•For solid dry soils: remove as much as possible
and then vacuum.
To clean, use the following instructions:
1. Saturate a lint-free, clean white cloth with water or
club soda.
2. Wring the cloth to remove excess moisture.
3. Start on the outside edge of the soil and gently rub
toward the center. Continue cleaning, using a clean
area of the cloth each time it becomes soiled.
4. Continue to gently rub the soiled area until the
cleaning cloth remains clean.
5. If the soil is not completely removed, use a mild
soap solution and repeat the cleaning process
that was used with plain water.
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If any of the soil remains, a commercial fabric cleaner or
spot lifter may be necessary. When a commercial
upholstery cleaner or spot lifter is to be used, test a
small hidden area for colorfastness first. If the locally
cleaned area gives any impression that a ring formation
may result, clean the entire surface.
After the cleaning process has been completed, a paper
towel can be used to blot excess moisture from the
fabric or carpet.
Instrument Panel, Vinyl, and Other
Plastic Surfaces
A soft cloth dampened with water may be used to
remove dust. If a more thorough cleaning is necessary,
a clean soft cloth dampened with a mild soap solution
can be used to gently remove dust and dirt. Never use
spot lifters or removers on plastic surfaces. Many
commercial cleaners and coatings that are sold to
preserve and protect soft plastic surfaces may
permanently change the appearance and feel of your
interior and are not recommended. Do not use silicone
or wax-based products, or those containing organic
solvents to clean your vehicle’s interior because
they can alter the appearance by increasing the gloss in
a non-uniform manner.Some commercial products may increase gloss on
your instrument panel. The increase in gloss may
cause annoying reflections in the windshield and even
make it difficult to see through the windshield under
certain conditions.
Care of Safety Belts
Keep belts clean and dry.
{CAUTION:
Do not bleach or dye safety belts. If you do, it
may severely weaken them. In a crash, they
might not be able to provide adequate
protection. Clean safety belts only with mild
soap and lukewarm water.
Weatherstrips
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 frequent application may be required. See
Part C: Recommended Fluids and Lubricants on
page 6-32.
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