
CAUTION
Turning the radiator pressure cap when the engine and radiator are
hot can allow steam and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will almost never h\
ave to
add coolant at the radiator. Never turn the radiator pressure cap-even a little-when the engine and radiator are hot.
Add coolant mix at the recovery tank, but be careful not to \
spill it.
You can be burned
if you spill coolant on hot engine parts. Coolant
mtains ethylene glycol, and
it will burn if the engine parts are hot
enough. Don’t spill coolant on a hot engine. ’
Radiator Pressure Cap
K2515
1
Your radiator pressure cap is a 15 psi (105 kPa) pressure-type cap
must be tightly installed to prevent coolant
loss and possible engine
damage from overheating. Be sure the arrows on the cap line up w
overflow tube on the radiator filler neck.
-
When you replace your radiator pressure cap, an ACa cap is recommended.
-
I
6-45
ProCarManuals.com

Service & Appearance Cam
Thermostat
Engine coolant temperature is controlled by a thermostat in the engine coolant
system. The thermostat stops the flow of coolant through the r\
adiator until the
coolant reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat is recommended.
Power Steering Fluid
K2630
How To Check Power Steering Fluid:
Unscrew the cap and wipe the dipstick with a clean rag. Replace the cap
and completely tighten it. Then remove the cap again and look at the fluid
level on the dipstick.
K2693
6-46
ProCarManuals.com

I I Power Rating I 1
Lamp or Bulb
Malfunction Indicator (“Service Engine
Quantity
at 12.8V, Watts Trade No.
Soon”)
“Diesel only
**Crew Cab Only tCanadian Vehicles only t0390
1 .7
74
Service Fuel Filter Lamp*
1 .7
74
Low Coolant Lamp*
1 .7 74 Glow Plugs Lamp*
1 .7
74
Upshift Indicator
1 .7
74
Service Replacement Part and Filter Recommendations
Engine
(VIN)
4.3 (Z)
5.0 (H)
5.7 (K)
6.2 (C)
6.2
(J)*
6.5 (F)*
7.4
(N)
-
Oil
Filter
PF51
PF35t
PF35t
PF35
PF35
PF35
PF35
-
Air
Cleaner
A1 78CW A348C
A348C
A644C A644C
A917C
A348C
PCV
Valve
CV789C
cv774c
cv774c
-
-
-
cv774c I I
tFour Wheel Drive Vehicles use a PF51
*Heavy
Duty Emission Engine
1,
Spark** Plugs
CR43TS
.CR43TS
.CR43TS
-
-
.CR43TS
oil filter
’*Use AC copper-cored resistor type spark plugs.
Fuel
Filter
GF481
GF481
GF481
TP 1
006
TP 1 006
TP1006
GF481
-I
RC36
RC36
RC32
RC32
RC32
RC36
t0039
6-99
ProCarManuals.com

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
8
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Recommended Fluids & Lubricants
NOTE: Fluids and lubricants identified below by name, part number or
specification may be obtained from your
GM Dealer.
USAGE I FLUID/LUBRICANT
Engine Oil
I
GM Goodwrench Motor Oil or equivalent for API Service SG
or SGlCE of the recommended viscositv.
Engine Coolant Mixture
of water and a good quality ethylene glycol base
antifreeze conforming
to GM-6038-M (GM Part No. 1052103).
Hydraulic Clutch System Hydraulic Clutch Fluid (GM Part
No. 12345347 or equivalent).
Hydraulic Brake Systems Delco Supreme
11
@ brake fluid (GM Part No. 1052535 or
DOT-3).
Parking Brake Cables
GM Lubricant (GM Part
No. 1052182) or equivalent.
Manual Steering Gear GM Power Steering
Fluid (GM Part
No. 1050017) or
Power Steering System Chassis grease meeting requirements of
NLGl Grade 2,
Automatic Transmission DEXRONB
HE Automatic Transmission Fluid (GM Part
No.
Catagory LB or GC-LB (GM Part No. 1052497).
equivalent conforming
to GM spec 9985010.
1051
855l.
Manual Transmission:
a. 5-Speed with Low Gear
b. Standard Transmission Fluid (GM Part
No. 12345349).
b. 5-Speed without Low Gear a.
CastrolB Syntorq or equivalent (GM Part
No.
1 2346074).
Differential:
a. Standard (Saginaw) Front
b. SAE-80W-90 gear lubricant (GM Part No. 1052271). b. Locking a.
SAE-80W-90 gear lubricant (GM Part
No. 1052271).
and Rear Axle
Transfer Case Gas Line De-lcer (GM Part
No. 1051516).
Gas Line DexronB
IIE Automatic Transmission
Fluid (GM Part No.
12345881).
Weather Strips
Category LB or GC-LB (GM Part
No. 1052497).
Chassis grease meeting requirements
of NLGl
Grade 2,
Clutch Fork Ball Stud Category
LB or GC-LB (GM Part
No. 1052497).
Shift Lever, and Propeller Shaft. Chassis grease meeting requirements
of NLGl Grade 2,
Column Shift, Transfer Case Spray-A-Squeek
(GM Part
No. 1052277).
(Continued next
page^
TO391
7-25
ProCarManuals.com

Scheduled Maintenance Services
Service Station Checks
It is important for you or a service station attendant to perform these
under-hood checks at each fuel
fill.
Check the engine oil level and add if necessary.
Check the engine coolant level in the recovery bottle and add if
necessary.
Check the windshield washer fluid level and add if necessary.
See these items in the Index
for information on how to check them.
7-28
ProCarManuals.com

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
ProCarManuals.com

1 Add-on Equipment ................... 6-94
I- Electronic Heatinghir Conditioning
(See "Heating")
Adding Coolant
... 5.12, 5.14. 6-44
... Engine I
Air Cleaner ................................ 6-31
Block Heater
.......... 2.19. 3.5. 6-26
Cold Weather Starting (Diesel)
.................... 2-1 7
Coolant
....... 5.12. 5-1 4. 6.42. 6-96
Coolant Temperature Gage
...... 2-88
Diesel
................................ 6.6. 6-1 9
Crankcase
.................................. 6-96
Fan Noise
.................................. 5-1 7
Noise Control System
.............. 6-1 9
.-Identification,
............................ 6-95
Oil .(See "Oil")
Overheating
................................. 5-9
Running While Parked
............. 2-35
Equipment, Add-on
...................... 6-69
Exhaust System
................ 2.34, 6-65
Exhaust
........................... 2.34,
6-65
Starting
............................ 2.12, 2-1 5
F
Fan Noise ...................................... 5-1 7
Filter
. Replacement Chart ............ 6-99
Finish Care
............................................ 6-88
Damage
..................................... 6-90
Automatic Transmission
........... 6-33
Brake
.......................................... 6-49
Coolant
............................ 5-1 2. 6-42
Front Axle
.................................. 6- 40
Hydraulic Clutch
....................... 6-37
Leak Check
................................ 6-52
Manual Transmission
................ 6-36
Power Steering
............ 1 ............ 6-46
Radiator
....................................... 5-1 4
Fluid
9-3
Rear Axle .................................. 6-41
Recommended Fluids
.............. 7-25
. Transfer Case ............................ 6-39
Windshield Washer.
................. 6-48
Fog Lamps
.................................... 2-54 .
Four-wheel Drive ............... 2.36, 6-39
Transfer Case
................ .2-37, 6-39
Front Axle
................................. 6-40
Fuel (Diesel Engines)
..................... 6.6
Cold Weather Operation
............ 6-7
Filter Replacement
........ 6-1 1, 6.13,
6-99
Fuel Requirements
..................... 6-6
Gage
........................ ; ................. 2-87
Running Out Of
........................ 6-10
Tank Capacity
........................... 6-97
Water in Fuel
.............................. 627
Fuel (Gasoline Engines)
................. 6-4
Filling Your Ta'nk
....................... 6-16
Foreign
. Countries ..................... 6-15
Gage
.......................................... 2-87
Gasolines for Cleaner Air
......... 6-5 A-
Fuses and Circuit
Breakers
............................ 6-64, 6-1 01 * .
Fuse Block ................................ 6-65 . . f
Headlights .................... 6.64, 6-100
Power Windows and Other
Trailer Wiring Harness
.. 6.64, 6-1 00
. Windshield Wipers ...... 6-64, 6-100
G
Gages ............................................ 2.87
Coolant Temperature Gage
..... 2-88
Fuel Gage
.................................. 2-87
Odometer
................................... 2-76
Oil Pressure Gage
..................... 2-89
Speedometer.
............................ 2-76
Tachometer
..................... 2.76, 2-78
Trip Odameter 2-77
Voltmeter
................................... 2-90
-
-.
I
Power Options ......... 6.64, 6-100 :
. ...........................
...
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