
What to Do with Used Oil:
I
I PAUTION
Used engine oil contains things that have caused skin cancer i\
n I
laboratory animals. Don’t let used oil stay on your skin fo\
r very long.
clnan your skin and nails with soap and water, or a good hand
c,,aner. Wash or properly throw away clothing or rags containing
used engine oil.
I
Used oil can be a real threat to the environment. If you change your own oil,
be sure to drain all free-flowing oil from the filter before disp\
osal. Don’t ever
dispose of
oil by putting it in the trash, pouring it on the ground, into sewers,
or into streams
or bodies of water. Instead, recycle it by taking it to a place
that collects used oil.
If you have a problem properly disposing of your used
oil, ask your dealer, a service station or a local recycling \
center for help.
Air Cleaner
I I
PO216
Refer to the Maintenance Schedule to determine when to replace \
the air
cleaner filter on diesel engines and the air cleaner filter an\
d crankcase ventilation filter on gasoline engines. See “Scheduled Mainten\
ance Services’’
in the Index.
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Automatic Transmission Fluid
When to Check and Change:
A good time to check your automatic transmission fluid level is when the
engine oil is changed. Refer
to the Maintenance Schedule to determine when
to change your fluid. See "Scheduled Maintenance Services" in the \
Index.
How to Check:
Because this operation can be a little difficult, you may choose to have this
done at a General Motors dealership Service Department.
If you
do it yourself, be sure to follow all the instructions here, or you could
get a false reading on the dipstick.
I Too much or too little fluid can damage your transmission. Too much can
nean that some of the fluid could come out and fall on hot engine parts,
itarting
a fire. Be sure to get an accurate reading if you check your
ransmission ftuid.
Wait at least
30 minutes before checking the transmission fluid level if you
have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic-especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid must be at normal operating temperature,
which is 180°F
to 200°F (82°C to 93°C).
To check the transmission fluid hot: Get the vehicle warmed up by driving
about
15 miles (24 km) when outside temperatures are above 50°F (1 0°C). If
it's colder than
50°F (lO°C), drive the vehicle in D (3rd gear) until the engine
temperature gage moves and then remains steady for ten minutes. Then
follow the hot check procedures.
To check transmission fluid cold: A cold check is made after the vehicle
has been sitting for eight hours or more with the engine
off and is used only
as a reference. Let the engine run at idle for five minutes
if outside
temperatures are 50°F (10°C) or more.
If it's colder than 50°F (lO"C), you
may have
to idle the engine longer. A hot check must follow when fluid is
added during a cold check.
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*
Senrice & Appearance Care
Manual Transmission Huld
When to Check:
the fluid in your manual transmission doesn't require changing.
How to 'Check:
Because this operation can be a :little difficult, you may cho\
ose to have this
done at your dealership Service Department.
t A good time to have it checked is when .the engine oil is changed. However,
If you do it yourself, be sure to follow' all the instructions here, or you could
get a false reading..
. . .. . . ... -
Too much or too little fluid can damage your transmission. Too much can
mean that some of the fluid could come out and fall on hot engine parts,
starting a fire. Be sure
to get an accurate reading if you check your
transmission fluid.
Check the fluid level only when your engine is
off, the vehicle is parked on a
level place and the transmission is cool enough for you to re\
st your fingers
on the transmission case.
Then, follow these steps:.
~ ~~ ~
1. Remove the filler plug.
K2471
2. Check that the lubricant level is up to the bottom of the filler- plug hole.
3. If the fluid level is good, install the plug and be sure it is fully seated. If
the fluid level is low, add more fluid as described in the next steps.
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Service & Appearance ,Care
Engine Coolant
r
PO593
The following explains your cooling system and how to add cool\
ant when it is low.
If you have a problem with -engine overheating, see “Engine
Overheating” in the Index.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 258°F (125°C).
Protect against rust and corrosion:
Help keep the proper engine temperature.
Let the warning lights and gages work as thiy should.
What to Use:
Use a ,mixture of clean water (preferably distilled), and antifreeze that meets
“GM Specification 6038-M,” which won’t damage aluminum p\
arts.
Also use
GM Engine Coolant Supplement (sealer) with a complete coolant change. If
you use these, you don’t need to add anything else.
,
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Service & Appearance Care
Cooling Systen
VIN
ENGINE
K 5.7L
H 5.0L
Z 4.3L
CODE
~13500
H.D.
6.2L C
6.2L
J
6.5L F
7.4L
N
w/3500
H.D.
Capacity
QUA
Without NC
10.9 Quarts (10.3 Liters)
17.5 Quarts (16.5 Liters)
17.5 Quarts (1 6.5 Liters)
26.5 Quarts (25 Liters)
25 Quarts (23.5 Liters)
25 Quarts (23.5 Liters)
26.5 Quarts (25 Liters) 23 Quarts (22 Liters)
26.5 Quarts (25 Liters)
ITITY*
With NC
10.9 Quarts (10.3 Liters)
18 Quarts (17 Liters)
18 Quarts (17 Liters)
27 Quarts (25.5 Liters)
25 Quarts (23.5 Liters)
25 Quarts 123.5 Liters)
26.5 Quarts (25 Liters)
25 Quarts (23.5 Liters)
28.5 Quarts (27 Liters)
*All quantities are approximate.
*After refill, the level
MUST be checked as outlined under “Engine Cooling
System” in Section
5.
TO036
Crankcase Capacity
ENGINE
5.0L
With Filter
Without Filter VIN CODE
7 Quarts (6.5 Liters) - ct 6.2L
5 Quarts (4.8 Liters) 4 Quarts (3.8 Liters) H
6.2L Jt - 7 Quarts (6.5 Liters)
6.5L
*All quantities are approximate. 7
Quarts (6.5 Liters)
- Ft
*After refill, the level MUST be checked as outlined under “Engine Oil
4.3L
5 Quarts (4.8 Liters)
4 Quarts (3.8 Liters) K 5.7L**
4.5 Quarts (4.3 Liters)
4 Quarts (3.8 Liters) Z
7.4L** 7
Quarts (6.6 Liters)
6 Quarts (5.7 Liters) N
And Filter Recommendations” in Section 5.
**Add one additional quart for C3500 HD Models.
toil filter should be changed at
EVERY oil change.
TO1 79
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Scheduled Maintenance Services
Explanation Of Scheduled Maintenance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to use are listed in this section. 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 ve\
hicle.
1.
ENGINE OIL AND OIL FILTER CHANGE* -ALWAYS USE SG OR
SGKE QUALITY, ENERGY CONSERVING II OILS OF THE PROPER
VISCOSITY. To determine the preferred viscosity oil for your vehicle’s
engine (e.g. SAE 5W-30 or 10W-30), see “Engine Oil” in the Index.
2. CHASSIS LUBRICATION -Lubricate the front suspension, king pin
bushings, steering linkage, transmission, and transfer case shift\
linkage,
parking brake cable guides, propshaft splines (2 wheel drive), brake
pedal springs, and clutch pedal springs at the intervals specified.
If you have a 3500 HD, lubricate the king pins and king pin bushings
every 1,500 miles
(2500 km) for Maintenance Schedule 1, or every 3,000
(5000 km) for Maintenance Schedule 2.
Ball joints and king pin bushings should not be lubricated unless their
temperature is
10°F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or they could be damaged.
Also, be sure to check
all the vehicle fluid levels at this time.
3.
CLUTCH FORK BALL STUD LUBRICATION -Lubricate the clutch fork
ball stud through the fitting on the clutch housing. Lubricant must be
added “sparingly” to the fitting, as only.
0066 Ib. (.003 kg) is required to
lubricate the ball stud surface.
Do not add lubricant more often than the
intervals in the Maintenance Charts.
Too much lubricant will damage
the clutch assembly.
4. ENGINE IDLE SPEED ADJUSTMENT (DIESEL ENGINES)* -Adjust to
the specifications shown on the underhood label. You must use
calibrated test equipment.
5. COOLING SYSTEM SERVICE* -Drain, flush and refill system with new
coolant. See “Engine Coolant’’ in the Index for the proper coolant and
mixture to use in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all hose clamps (except constant tension \
clamps).
Remove debris and clean the outside
of the radiator and air conditioning
condenser. Wash the radiator neck.
To ensure proper operation, pressure
test the radiator and cap.
* An Emission Control Service
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23. EXHAUST PRESSURE REGULATOR VALVE INSPECTION* -Check that
the valve works properly. Correct any binding. Inspect hoses fo\
r cracks, chafing or decay. Replace parts as needed.
24.
TIRE AND WHEEL ROTATION AND INSPECTION -For proper wear
and maximum tire life, rotate tires at the first
6,000 miles (1 0 000
kilometers) for Schedule I (t) or 7,500 miles (12 500 kilometers) for
Schedule
II (.) and then every 15,000 miles (25 000 kilometers)
thereafter. Follow the instructions and patterns shown in Section 6.
Check tires for uneven wear or damage.
If irregular or premature wear is
apparent, check wheel alignment. Also, check for damaged wheels.\
See
“Tires” in the Index for more information.
For dual wheels, whenever the vehicle, wheels, or fasteners are new,
have the wheel fastener torque set at the first 100,
1,000 and 6,000
miles (160, 1600 and 10
000 km).
For 3500 H.D. Models, block the tires opposite those being removed to
keep the vehicle from rolling.
25.
DRIVE AXLE SERVICE -Check readfront axle fluid level and add as
needed. Check constant velocity joints and axle seals for leaki\
ng.
Locking differential-Drain fluid at first oil change and refill. Check
fluid level and add as needed at subsequent oil changes.
In dusty
areas, or trailer towing applications drain fluid at every 15,0\
00 miles
(24 135 kilometers) and refill$
every oil change. In dusty areas, or trailer towing applications, drain
fluid every 15,000 miles
(24 135 kilometers) and refi1l.t
More frequent lubrication may be required on heavy-duty or off-road
use.
Standard differential -Check fluid level and add as needed at
26.
BRAKE SYSTEM INSPECTION -When the engine oil is changed,
inspect the lines and hoses for proper hookup, binding, leaks, \
cracks,
chafing, etc. Check the parking brake adjustment, and the fluid level in
the master cylinder.
A low fluid level can indicate worn disc brake pads
which may need to be sewiced.t
*An Emission Control Service
tA fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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Scheduled Maintenance Services
Periodic Maintenance Inspections
Listed below are inspections and services which should be perfo\
rmed at least
twice a year (for instance each spring or fall).
You should let your GM
dealer’s service department or other qualified service center \
do these jobs.
Make sure any necessary repairs are completed at once.
Steering and Suspension lnspectiont -Inspect front and rear suspension
and steering system for damaged, loose or missing parts, signs \
of wear or
lack of lubrication. Inspect power steering lines and hoses for proper \
hook-up,
binding, leaks, cracks, chafing, etc. (On vehicles equipped wit\
h manual
steering gear, check for seal leakage.) Lubricate the steering linkage.
Accelerator Control System -Lubricate all pivot points with engine oil,
except the
TBI throttle shaft. Remove all external deposits from the injector
pump face cam on 6.2L and 6.5L engines.
Do this when the engine is cold
and not running.
Do not oil any accelerator or cruise control cables. Replace
any cables that have high effort or excessive wear.
Exhaust System Inspection -Inspect the complete system including the
three-way catalytic converter. Inspect the body near the exhaust\
system. Look
for broken, damaged, missing or out-of-position parts, as well \
as, open
seams, holes, loose connections or other conditions which could \
cause a heat buildup in the floor pan or could let exhaust fumes seep into the passenger
compartments.
Drive Axle Service -Check readfront axle fluid level and add as needed.
Check constant velocity joints and axle seals for leaking.
Transfer Case (four-wheel drive) lnspectiont -Every 12 months or at oil
change intervals, check front axle and transfer case and add l\
ubricant when necessary. Oil the control lever pivot point and all exposed c\
ontrol linkage.
Check vent hose at transfer case for kinks and proper installa\
tion. More
frequent lubrication may be required on heavy-duty or off-road use.
tA fluid loss in these systems may indicate a problem. Have them inspected
and repaired at once.
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