Page 291 of 486
Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when
it is running, you could cause
serious damage
to it. If you ever clean the engine, clean it only
when it
is cold.
Engine Oil (Gasoline Engines)
It’s 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.
6-14
ProCarManuals.com
Page 333 of 486

NOTICE:
Don’t let anyone tell you that underinflation or overinflation is
all right. It’s not.
If your tires don’t have enough air
(underinflation) you can get:
Too much flexing
0 Too much heat
Tire overloading
Bad wear
Bad handling
0 Bad fuel economy.
If your tires have too much air (overinflation), you can get:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
When to Check
Check your tires once a month or more. Also, check the tire pressure of the
spare tire.
How to Check
Use a good quality pocket-type gage to check tire pressure. Simply looking
at the tires will not tell you the pressure, especially if you have radial tires
- which may look properly inflated even if they’re underinflated.
If your tires have valve caps, be sure
to put them back on. They help prevent
leaks by keeping
out dirt and moisture.
Tire Inspection and Rotation
Tires should be inspected every 6,000 to 8,000 miles (10 000 to 13 000 km)
for any signs
of unusual wear. If unusual wear is present, rotate your tires as
soon as possible and check wheel alignment. Also check for damaged tires
or wheels. See “When it’s Time for New Tires’’ and “Wheel Replacement”
later
in this section for more information.
6-56
ProCarManuals.com
Page 354 of 486
Engine Identification - Diesel Engines
Engine Type
VTN Code
Fuel System
Wheel Nut Torque
MODEL
C 1500
K 1500, C-K 2500
C-K 2500
6.5L
V8
S
Turbo Diesel
DESCRIPTION
5 bolts (14mm)
6 bolts
(1 4mm)
8 bolts ( 14mm)
Cooling System Capacity
ENGINE
5.7L
6.5L
6.5L 7.4L
VIN
K
S
F
N
6.5L
V8
F
Turbo Diesel
TORQUE
120 ft. Ibs. ( 160 N*m)
120 ft. Ibs. (1 60 Nom)
I20
ft. lbs. ( 160 Nom)
QTY Without
Rear Heater*
1 7.5 Quarts
( 16.5 Liters)
23.5 Quarts (22.2 Liters)
23.5 Quarts
(22.2 Liters)
25 Quarts
(23.5
Liters)
QTY With
Rear Heater4’
20 Quarts (1 9
Liters)
27.5 Quarts (26
Liters)
27.5 Quarts (26
Liters)
27.5 Quarts (26
Li ters)
After refill. the level MUST be checked
as outlined under “Engine Cooling
System” in Section 5.
‘$All quantities are approximate.
6-77
ProCarManuals.com
Page 355 of 486
Crankcase Capacity
ENGINE
5.7L
6.5L
6.5L
7.4L
VIN
K
S
F
N
QUANTITY WITH
FILTER?
5 Quarts (4.8 Liters)
7 Quarts (6.5 Liters)
7 Quarts (6.5 Liters)
7 Quarts (6.5 Liters)
After refill, the level
MUST be checked as outlined under “Engine Oil And
Filter Recommendations”
in Section 5.
All quantities are approximate.
?Oil filter should be changed at EVERY oil change.
Fuel Tank Capacity
TYPE
Gasoline/Diesel
Utility Models - Standard
Suburban
- Standard
QUANTITY
30 Gallons ( I 1 3 Liters)
42 Gallons
( I59 Liters)
All quantities are for a completely dry tank and are approximate.
Service Replacement Part and Filter
Recommendations
- Gasoline Engines
Engine
VIN
Oil Filter
Air Cleaner Filter
PCV Valve
Spark Plugs”
Fuel Filter
Radiator Cap
5.7L
K
PF1218T A348C
cv774c
CR43TS
GF48 1
RC36
?Four Wheel Drive Vehicle
- use a PF52 oil filter
*Use AC copper-cored resistor type spark plugs
7.4L
N
PF1218
A348C
cv774c
.CR43TS GF48
1
RC36
ProCarManuals.com
Page 356 of 486
Service Replacement Part and Filter Recommendations
- Diesel Engines
Engine
VIN
Oil Filter
Air Cleaner
Fuel Filter
Surge Tank
Cap
6SL
S
PF1218
A1236C
TP 1006
RC33
6.5L
F
PF1218
A 1236C
TP 1 006
RC33
Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same. If the air conditioning
system
in your vehicle needs refrigerant, be sure the proper refrigerant is
used.
If you’re not sure, ask your GM dealer. For additional information, see
your “Warranty and Owner Assistance Information’’ booklet.
NOTICE:
R-134A refrigerant is not compatible with R-12 refrigerant in
an air conditioning system. R-12 in an R-134A system will cause
compressor failure, refrigerant oil sludge, or poor air
conditioning system performance.
Air Conditioning Refrigerant Capacity
TYPE
Refrigerant R-134A
Refrigerant
R- 134A
QTY
Front A/C 3.0 lbs. (1.360 kg)
Front and Rear A/C 4.25 Ibs. (1.927
kg)
6-79
ProCarManuals.com
Page 368 of 486
Every 30,000 Miles (50 000 km)
Air Cleaner Filter Replacement
Spark Plug Replacement
Fuel Filter Replacement
Cooling System Service (or every
24 months, whichever occurs first)
Every 50,000 Miles (83 000 km)
Automatic Transmission Service (severe conditions only)
Every 60,000 Miles (100 000 km)
Engine Accessory Drive Belt Inspection
Spark Plug Wire Inspection
Engine Timing Check Fuel Tdnk, Cap and Lines Inspection
I
Schedule lI Definition - Gasoline Engines With Light Duty
Emissions
Follow Schedule 11 orzly if none of the conditions from Schedule I is true.
Every 7,500 Miles (12 500 km)
Engine Oil and Filter Change (or every 12 months, whichever occurs first)
Chassis Lubrication (or every
12 months, whichever occurs first)
Drive
Axle Service
At 7,500 Miles (12 500 km) - Then Every 15,000 Miles (25 000 km)
Tire Rotation
7-S
ProCarManuals.com
Page 369 of 486

Every 30,000 Miles (50 000 km)
Cooling System Service (or every 24 months, whichever occurs first)
Spark Plug Replacement
Fuel Filter Replacement
Air Cleaner Filter Replacement Front Wheel Bearing Repack
Every 50,000 Miles (83 000 km)
Automatic Transmission Service (severe conditions only)
Every 60,000 Miles (100 000 km)
Spark Plug Wire Inspection
Engine Accessory Drive Belt Inspection
Fuel Tank, Cap and Lines Inspection
Engine Timing Check
Schedule 1 Definition - Gasoline Engines With Heavy Duty
Emissions
Follow Maintenance Schedule I if any one of these is true for your vehicle:
e
e
e
e
Most trips are less than 5 to 10 miles (8 to 16 km). This is particularly
important when outside temperatures are below freezing.
Most trips include extensive idling (such as frequent driving
in stop and
go traffic).
You operate
your vehicle in dusty areas or off-road frequently.
You frequently tow
a trailer or use a carrier on top of your vehicle.
Schedule
I should also be followed if the vehicle is used for delivery
service, police, taxi, or other commercial application.
Schedule I Intervals - Gasoline Engines with Heavy Duty
Emissions
Every
3,000 Miles (5 000 km)
Engine Oil and Filter Change (or every 3 months, whichever occurs first)
Chassis Lubrication (or every
3 months, whichever occurs first)
Drive Axle Service
7-6
ProCarManuals.com
Page 370 of 486

At 6,000 Miles (10 000 km) - Then Every 12,000 Miles (25 000 km)
Tire Rotation
Every 12,000 Miles (20 000 km)
Air Cleaner Filter Inspection, if Driving in Dusty Conditions
Front Wheel Bearing Repack (or at Each Brake Relining) (2-Wheel Drive Only)
Fuel Filter Replacement
Engine Accessory Drive Belt Inspection
Shields and Underhood Insulation Inspection
Thermostatically Controlled Engine Cooling Fan Check (or every
12 months, whichever occurs first)
Every 24,000 Miles (40 000 km)
Cooling System Service (or every 24 months, whichever occurs first)
Air Cleaner Filter Replacement
Engine Timing Check
Thermostatically Controlled Air Cleaner Inspection
Air Intake System Inspection
Every 27,000 Miles (45 000 km)
Spark Plugs Replacement
Every 50,000 Miles (83 000 km)
Automatic Transmission Service
Every 60,000 Miles (100 000 km)
Spark Plug Wire Inspection
Exhaust
Gas Recirculation (EGR) System Inspection
Fuel
Tmk, Cap and Lines Inspection
Evaporative Control System Inspection
Electronic Vacuum Regulator Valve (EVRV) Inspection
7-7
ProCarManuals.com