
Engine Fan Noise
This 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 every day
driving conditions the clutch is not engaged. This improves fue\
l economy and
reduces fan noise. Under heavy vehicle loading, trailer towing andlor high
outside temperatures, the fan speed increases when the clutch e\
ngages.
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.
If a Tire Goes Fiat
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 “blowout,” 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, 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 your tire goes flat, the next part shows how to use your jacking equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driv\
ing slowly to a
level place. Turn on your hazard warning flashers.
5-1 7
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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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1 CAUTION
4 Adding only plain water to your cooling system can be dangerous.
Plain water, or some other liquid like alcohol, can boil before th(
)per coolant mix will. Your vehicle’s coolant warning system is set
for the proper coolant mix. With plain water or the wrong mix\
, your
engine could get too hot but you wouldn’t get the overheat warning.
Your engine could catch fire and you or others could be burned. Use
a
50/50 mix of clean water and a proper antifreeze.
NOTICE
If you use an improper coolant mix, your engine could overheat an\
d 1:
badly damaged. The repair cost wouldn’t be covered by your warranty. 1
much water in the mix can freeze and xk +?e t line radiator, heater
core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for the prope\
r way to add
coolant.
If you have the low coolant warning system, refer to the General Motors
Service Manual or see your dealer for the proper coolant
fill procedure. (To
purchase a Service Manual, see “Service Publications’’ in the Index.) Using
the wrong
fill procedure can cause a low coolant warning indication.
If you have to add coolant more than four times a year, have your dealer
check your cooling system.
If you use the proper coolant, you don’t have to add extra inhibitors or
additives which claim to improve
the system. These can be harmful.
-
NOTICE .I
6-43
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Service & Appearance Care
Windshield Wiper Blade Inserts
I -
r
PO232
To replace the windshield wiper blade insert, lift the wiper arm and rotate the
blade until it is facing away from the windshield. Unlatch the\
end of the insert
from the holding clips. Remove the insert and slide a new one\
in place.
Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditi\
oning system
to be sure it has not lost any cooling ability.
If you think the system is not
working properly, have your dealership check it out as soon as\
possible.
The air conditioning will not work when the temperature is bel\
ow 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the su\
rface under the
vehicle
for water, oil, fuel or other fluids. Water dripping from the air
conditioning system after it has been used is normal, If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lubrication
Accelerator Control System
Your maintenance schedule will tell you how often the accelerator linkage
pivot points must be lubricated. See “Recommended Fluids and \
Lubricants” in
the Index for the proper lubricant to use.
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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
7-1
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Scheduled Maintenance Services
13. EGR SYSTEM INSPECTION* -Conduct EGR SYSTEM CHECK as
described in the Service Manual.
14. ELECTRONIC VACUUM REGULATOR VALVE (EVRV) INSPECTION*
-Inspect filter for excessive contamination or plugging. If required, clean
element with a solution of biodegradable soap and water, let
dry and
reinstall element.
15. ENGINE TIMING CHECK AND DISTRIBUTOR CHECK (SOME
MODELS)”
-Adjust timing to underhood label specifications. Inspect the
inside and outside of the distributor cap and rotor for cracks, carbon
tracking and corrosion. Clean or replace as needed.
cap and lines for damage or leaks. Remove fuel cap, inspect g\
asket for
an even filler neck imprint, and any damage. Replace parts as \
needed.
16. FUEL TANK, CAP AND LINES INSPECTION* -Inspect the fuel tank,
17. THERMOSTATICALLY CONTROLLED AIR CLEANER INSPECTION*
A-(If so equipped.) Inspect all hoses and ducts for proper hookup.
Make sure valve works properly.
Look for cracks, fraying, wear, and proper tension. Adjust or replace as
needed.
19. EVAPORATIVE CONTROL SYSTEM (ECS) INSPECTION* -Check all
fuel and vapor lines and hoses for proper hookup, routing, and\
condition.
Check that the purge valve works properly,
if equipped. Replace as
needed.
18. ENGINE ACCESSORY DRIVE BELT(S) INSPECTION* --Inspect belts.
20. SHIELDS AND UNDERHOOD INSULATION INSPECTION Am-Inspect
shields and underhood insulation for damage or looseness. Adjust\
or
replace as required.
21. AIR INTAKE SYSTEM INSPECTlONAWCheck the air intake system
installation to see that gaskets are seated properly and all hose
connections, fasteners, and other components are tight. Also check to be
sure that the air cleaner housing is properly seated, that the\
cover fits
tightly, and the wing nuts are tight. Tighten connections and \
fasteners or
replace damaged parts as required.
22. THERMOSTATICALLY CONTROLLED ENGINE COOLING FAN INSPECTI0NA.-(If
so equipped.) With the engine off and below
normal operating temperature, check to see that the fan can be rotated
by hand on fluid coupling or viscous drives. Replace as necessary.
*An Emission Control Service
AAlso a Noise Emission Control Service
.Applicable only to vehicles
sold in the United States
7-20
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C
Camper Wiring Harness .............. 2-91
Capacities/Specification Charts .. 6-95
Cassette Tape Player
Catalytic Converter
...................... 6-65
Certificationnire Label
................. 6-67
Changing
A Flat Tire ........ 5.17. 5-23
Chemical Paint Spotting
.............. 6-90
Child Restraints
Cigarette Lighter/Ashtrays
........... 2-62
Circuit Breakers (See “Fuses”)
Cleaning (See
“Audio Systems”)
(See “Safety Belts”)
Finish Care
................................ 6-88
Glass
.......................................... 6-87
Inside of Vehicle
....................... 6-85
Instrument Panel. Top
............. 6-87
Outside of Vehicle
.................... 6-88
Special Problems
...................... 6-86
Vinyl
or Leather ........................ 6-87
Wheels and Tires
..................... 6-89
Windshield
................................ 6-88
Clock
................................... 3-1 2. 3-1 5
Computer Command Control
System
..................................... 6-66
Conversion to Chassis Cab
........ 6-72
Coolant (See “Engine”)
Cooling System
............................ 5-1 1
Capacity
.................................... 6-96
Crankcase Capacity
...................... 6-96
Cruise Control
............................... 2-47
Increase Speed
......................... 2.50
On Hills ...................................... 2-51
Passing
...................................... 2-51
Resume
..................................... 2-49
Set
.............................................. 2-48
To Get Out Of
.......................... 2-52
Cup Holder
.................................... 2-65
Customer Assistance for the
Customer Satisfaction Procedure.8-2 Reduce Speed
.......................... 2-51
Hearing
or Speech Impaired .... 8-3
D
Daytime Running Lights
(Canada Only)
.................... 2.55. 2-84
Indicator Light
............... 2.55. 2-84
Diesel Fuel (See “Fuel”)
Dome Lights
................................. 2-56
Doors
............................................... 2-5
Driving Locks
............................................ 2-6
Across an Incline
..................... 4-33
After Off-Road Driving
............ 4-36
At Night
.......................... 4.36. 4-38
Backing Up
............................... 4-59
Defensive
................................... 4-10
Downhill
..................................... 4-31
Freeway
..................................... 4-43
High Beams
.............................. 4-37
Highway Hypnosis
................... 4-46
Hydroplaning
............................. 4-39
In Blizzard
................................. 4-54
In City
....................................... 4-42
In Fog. Mist and Haze
. 4.41 . 4-42
In Rain
............................ 4.38. 4-40
In Sand. Mud. Ice.
Or Snow .................................. 4-34
In Water
.................................... 4-35
Long Distance
.......................... 4-45
Loss of Control
........................ 4-24
Night Vision
.............................. 4-37
Off-Roading
............................... 4-25
On Curves
................................. 4-20
On Grades
................................. 4-60
On Hill and Mountain Roads
. 4-47
On Off-Road Hills
.................... 4-28
On Snow
or Ice .. 2.15. 4.52. 4-55
Passing
............................ 4.22. 4-59
Skidding
..................................... 4-24
Stuck in Deep Snow
..... 4.54. 5-33
Through Water
.............. 2.15. 4-35
Uphill
.......................................... 4-29
Winter
........................................ 4-52
With a Trailer
............................ 4-55
Drunken Driving
........................... 4-11
9-2
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