Page 235 of 398
yellowblue
5-19
6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX
-COOL coolant mixture
through the filler neck until the level reaches the
base of the filler neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap. Be sure the
arrows on the pressure cap line up like this.
Page 236 of 398

yellowblue
5-20
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 fan is spinning slower and 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 as the
clutch more fully 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 partially disengages.
You may also hear this fan noise when you start
the engine. It will go away as the fan clutch
partially disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº 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 ªblowout,º 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, the next part shows how to use your
jacking equipment to change a flat tire safely.
Page 276 of 398

yellowblue
6-22
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:
Give freezing protection down to
-34F (-37C).
Give boiling protection up to 265F (129C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you use
only DEX
-COOL (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX
-COOL is not
covered by your new vehicle warranty.
What to Use
Use a mixture of one-half clean, drinkable water and
one
-half DEX-COOL coolant which won't damage
aluminum parts. If you use this coolant mixture, you
don't need to add anything else.
Page 277 of 398

yellowblue
6-23
CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle's coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
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 mixture of clean, drinkable water and
DEX
-COOL coolant.
NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
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.
Page 303 of 398
yellowblue
6-49
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque, see ªWheel Nut Torqueº
in the Index.
See ªChanging a Flat Tireº in the Index for
more information.Used Replacement Wheels
CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used or
how far it's been driven. It could fail suddenly
and cause an accident. If you have to replace a
wheel, use a new GM original equipment wheel.
Page 321 of 398

yellowblue
6-67 Wheel Nut Torque
MODEL TORQUE
All
140 lb
-ft (190 N´m)
Cooling System Capacity (Approximate)
ENGINE VIN QTY Without Rear Heater QTY With Rear Heater
ªVORTECº 4300 V6 W 11.0 Quarts (10.4 L) 14.0 Quarts (13.2 L)
ªVORTECº 5000 V8 M 17.0 Quarts (16.0 L) 20.0 Quarts (18.9 L)
ªVORTECº 5700 V8 R 17.0 Quarts (16.0 L) 20.0 Quarts (18.9 L)
ªVORTECº 7400 V8 J 23.0 Quarts (21.8 L) 26.0 Quarts (24.6 L)
After refill, the level MUST be checked as outlined under ªEngine Cooling Systemº in Section 5.
Crankcase Capacity (Approximate)
ENGINE VIN Quantity With Filter
ªVORTECº 4300 V6 W 4.5 Quarts (4.3 L)
ªVORTECº 5000 V8 M 5.0 Quarts (4.8 L)
ªVORTECº 5700 V8 R 5.0 Quarts (4.8 L)
ªVORTECº 7400 V8 J 6.0 Quarts (5.6 L)
After refill, the level MUST be rechecked. Add enough engine oil so that the fluid is within the proper operating
range. Variation in oil filter size and oil cooler drainback can cause different fill levels. See ªEngine Oilº in the Index.
*Add one additional quart for RPO 5Z1 and RPO KL5 Models.
Page 329 of 398

Scheduled Maintenance
yellowblue
7-5
Short Trip/City Definition
Follow the Short Trip/City Scheduled Maintenance if
any one of these conditions is true for your vehicle:
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).
Most trips are through dusty areas.
You frequently tow a trailer or use a carrier on top of
your vehicle.
If the vehicle is used for delivery service, police, taxi
or other commercial application.
One of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil to break
down sooner.
Short Trip/City Intervals
Every 3,000 Miles (5 000 km): Engine Oil and Filter
Change (or 3 months, whichever occurs first). Chassis
Lubrication (or 3 months, whichever occurs first).
Drive Axle Service (or 3 months, whichever
occurs first).
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Engine Air Cleaner
Filter Inspection, if driving in dusty conditions.
Gasoline Engine Only: Noise Shields Inspection
(GVWR above 10,000 lbs. only). Diesel Engine Only:
Shields and Underhood Insulation Inspection. Diesel
Engine Only: Thermostatically Controlled Engine
Cooling Fan Check (or every 12 months, whichever
occurs first). Diesel Engine Only: Air Intake System
Inspection. Front Wheel Bearing Repack (or at each
brake relining, whichever occurs first).
Every 24,000 Miles (40 000 km): Diesel Engine Only:
Fuel Cap Replacement, if driving in dusty conditions.
(Continued)
Page 330 of 398

Scheduled Maintenance
yellowblue
7-6
Short Trip/City Intervals
Every 30,000 Miles (50 000 km): Engine Air Cleaner
Filter Replacement. Fuel Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over 8600 GVWR
or driven under severe conditions or equipped with
diesel engine).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. 7.4L Gasoline Engine (Except
California): Fuel Tank, Cap and Lines Inspection.
If Equipped: Exhaust Gas Recirculation System
Inspection. Gasoline Engine Only: Evaporative
Control System Inspection. Diesel Engine Only:
Crankcase Depression Regulator Valve (CDRV)
System Check.
Short Trip/City Intervals
Every 100,000 Miles (166 000 km): Gasoline Engine
Only: Spark Plug Wire Inspection. Gasoline Engine
Only: Spark Plug Replacement. Gasoline Engine
Only: Automatic Transmission Service (normal
conditions). Gasoline Engine Only: Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every 60 months, whichever occurs first).
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.