How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at the FULL COLD mark
or higher, add a 50/50 mixture of clean, drinkable water
and DEX-COOL
®coolant at the coolant surge tank,
but be sure the cooling system, including the coolant
surge tank pressure cap, is cool before you do it.
SeeEngine Coolant (Caterpillar
®Diesel Engines) on
page 5-44orEngine Coolant (Gas and
DURAMAX
®/Isuzu 7.8L L6 Engines) on page 5-44for
more information.
If no coolant is visible in the surge tank, add coolant as
follows:
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
CAUTION: (Continued)
CAUTION: (Continued)
cap when the cooling system, including the
coolant surge tank pressure cap, is hot. Wait
for the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The
engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
5-52
4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the engine
cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches slightly above the FULL
COLD mark.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
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 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 when the clutch
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
disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
SeeScheduled Maintenance on page 6-5to determine
when to check your power steering fluid.
5-54
(21)= Inspect parking brake drum and linings for wear
or cracks and check linkage and adjustment.
(22)= Wheel bearing service:
•Grease type — Clean, inspect, and lubricate with
the proper wheel bearing grease at designated
intervals or when hubs are removed. SeePart C:
Recommended Fluids and Lubricants on page 6-31.
•Oil-filled type — Some wheel bearings are
lubricated by axle lubricant. When you have oil-filled
hubs, use lubricant identical to that used in the
axle. Lubricant change intervals are the same for
front and rear axles. However, you must maintain
the proper oil level between change intervals.
SeeFront Wheel Bearings with Oil-Filled Hubs on
page 5-81andPart C: Recommended Fluids
and Lubricants on page 6-31.
(23)= Check the air intake system installation to see
that gaskets are seated properly and all hose
connections, fasteners, and other components are tight.
Tighten connections and fasteners or replace parts as
required.
(24)= Evaporative Control System Service, if equipped:
Check all fuel and vapor lines and hoses for proper
connections and correct routing (or every 24 months,
whichever occurs first). Replace parts as needed.(25)= Replace spark plugs. Inspect wires for damage.
Check the wire boot and boot heat shield fit at spark
plugs and coil. Replace parts as needed.
(26)= Check the fuel tank, fuel cap and fuel lines for
damage which could cause leakage. Inspect fuel cap for
correct sealing ability and any indications of damage.
Check fuel cap gasket for even filler neck imprint.
Replace parts as needed.
(27)= Check Exhaust Gas Recirculation (EGR) system
as described in the service manual. SeeService
Publications Ordering Information on page 7-10.
(28)= Inspect Electronic Vacuum Regulator Valve
(EVRV) filter for excessive contamination or plugging.
If needed, clean filter with solution of soap and water, let
dry and install.
(29)= Drain, flush, and refill cooling system. This
service can be complex; you should have your
dealer/retailer perform this service. SeePart C:
Recommended Fluids and Lubricants on page 6-31for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap, and neck. Pressure test cooling system
and pressure cap. For Caterpillar
®diesel engines,
always refer to the Caterpillar®Diesel Engine
Operation & Maintenance Manual for coolant
recommendations and change intervals.
6-23
Part B: Owner Checks and Services
Listed in this part are owner checks and services
which should be performed at the intervals specified to
help ensure the safety, dependability and emission
control performance of your vehicle.
For your safety and that of others, any of the
safety-related components that may have been
damaged in an accident should be checked and any
needed repairs made before operating the vehicle.
At the minimum, these routine checks should be made
every 6 months or 6,000 miles (10 000 km), whichever
occurs first. Whenever repairs are needed, have
them completed before operating the vehicle.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by your warranty.Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil (Caterpillar
®Diesel Engine)
on page 5-23orEngine Oil (Gasoline Engine) on
page 5-24orEngine Oil (DURAMAX
®Diesel Engine) on
page 5-28orEngine Oil (Isuzu Diesel Engine) on
page 5-32.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
(Caterpillar®Diesel Engines) on page 5-44orEngine
Coolant (Gas and DURAMAX®/Isuzu 7.8L L6 Engines)
on page 5-44.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the windshield
washer fluid reservoir and add the proper fluid if
necessary. SeeWindshield Washer Fluid on page 5-55.
Tire In ation Check
Check tire inflation cold. Make sure the tires are inflated
to the correct pressures. SeeLoading Your Vehicle
on page 4-21andInflation - Tire Pressure on page 5-82.
6-26
Part C: Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number, or specification can be obtained from your
dealer/retailer.
Usage Fluid/Lubricant
Engine Oil
(Gasoline
Engine)Engine oil which meets
GM Standard GM6094M and
displays the American Petroleum
Institute (API) Certified for Gasoline
Engines starburst symbol. To
determine the proper viscosity for
your vehicle’s engine, see “Engine
Oil” in the Index.
Engine Oil
(DURAMAX
®/
Isuzu Diesel
Engines)Engine oils with the letters CJ-4 are
required for your vehicle. The CJ-4
designation can appear either alone
or in combination with other
American Petroleum Institute (API)
designations, such as API CJ-4/SL.
These letters show API levels of
quality. To determine the preferred
viscosity for your vehicle’s diesel
engine, see “Engine Oil” in the Index.
Engine Oil
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine oil
recommendations.
Usage Fluid/Lubricant
Engine Coolant
(Caterpillar
®
Diesel Engine)See the Caterpillar
®Operation &
Maintenance Manual for engine
coolant recommendations.
Engine Coolant
(Gasoline
Engine &
DURAMAX
®/
Isuzu Diesel
Engines)50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant
(Caterpillar®Diesel Engines) on
page 5-44orEngine Coolant
(Gas and DURAMAX
®/Isuzu 7.8L
L6 Engines) on page 5-44.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
Washer SolventOptikleen
®Washer Solvent.
Clutch Bearing
LubricantClutch Bearing Lubricant
(GM Part No. 12378484 or
equivalent NLGI #3 consistency).
Exhaust Brake
Ball Joint Cap
LubricantHigh-Temperature Grease
(GM Part No. U.S. 1051344, in
Canada 903037) or NLGI #3
consistency.
Power Steering
SystemDEXRON
®-VI Automatic
Transmission Fluid.
Manual
TransmissionSynthetic Manual Transmission Fluid
(GM Part No. U.S. 88861952, in
Canada 88861953).
6-31
L
Lamps
Dome........................................................3-16
Marker.......................................................3-16
Reading.....................................................3-17
Lap Belt........................................................1-27
Lap-Shoulder Belt...........................................1-24
LATCH System
Child Restraints...........................................1-40
Light
Airbag Off..................................................3-29
Airbag Readiness........................................3-28
Antilock Brake System Warning.....................3-34
Brake System Warning.................................3-32
Change Engine Oil......................................3-38
Change Fuel Filter Warning..........................3-44
Charging System.........................................3-30
Check Gages Warning.................................3-42
Daytime Running Lamps Indicator..................3-41
Diesel Particulate Filter Warning....................3-45
Differential Lock Indicator..............................3-40
Engine Overspeed Warning...........................3-39
Engine Shutdown Warning............................3-39
Exhaust Brake Indicator................................3-40
Highbeam On.............................................3-41Light (cont.)
Low Coolant Warning...................................3-35
Low Oil Level.............................................3-38
Low Washer Fluid Warning...........................3-42
Malfunction Indicator....................................3-36
Power Take-Off...........................................3-42
Range Inhibit Warning Indicator.....................3-32
Reduced Engine Power................................3-41
Safety Belt Reminders..................................3-27
Service Transmission Warning.......................3-31
Trailer Antilock Brake System Warning............3-34
Wait to Start Indicator..................................3-36
Water in Fuel Warning.................................3-44
Lighting
Entry.........................................................3-17
Lights
Exterior Lamps............................................3-14
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-15
Loading Your Vehicle.......................................4-21
Locks
Door........................................................... 2-6
Power Door.................................................. 2-7
Loss of Control...............................................4-12
Low Coolant Warning Light..............................3-35
Low Washer Fluid Warning Light.......................3-42
7