2003 GMC SIERRA DENALI radiator

1. Park the vehicle on a
level surface. You can
remove the coolant
surge tank pressure
cap when the cooling
system, including
the coolant surge tank pressure cap and
upper radiator hose,
is no longer hot.
2. Turn the pressure cap slowly counterclockwise (left)
about one full turn.
If you hear a hiss, wait for that to
stop.
A hiss means there is still some pressure left.
3. Then keep turning the pressure cap slowly, and
remove
it.
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4. Then fill the coolant surge tank with the proper
mixture, to the FULL COLD mark. 5. 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 the FULL COLD mark.
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90,000 Miles (150 000 km)
0 Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
0 Replace fuel filter. An Emission Control Service. (See
Footnote
t.)
0 Replace engine air cleaner filter. An Emission
Control Service.
0 Rotate tires. See Tire Inspection and Rotation on
page 5-62
for proper rotation pattern and additional
information.
(See footnote +.)
97,500 Miles (162 500 km)
c[I Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
page 5-62 for proper rotation pattern and additional
information.
(See footnote +.)
0 Rotate tires. See Tire Inspection and Rotation on
100,000 Miles (166 000 km)
0 Inspect spark plug wires. An Emission Control
0 Replace spark plugs. An Emission Control Service.
Service.
0 Change automatic
transmission fluid and filter if the
vehicle
is mainly driven under one or more of these
conditions:
- In heavy city traffic where the outside
temperature regularly reaches
90°F (32°C) or
higher.
- In hilly or mountainous terrain.
- When doing frequent trailer towing.
- Uses such as found in taxi, police or delivery
service.
0 If you haven’t used your vehicle under severe service
conditions listed previously and, therefore, haven’t
changed your automatic transmission fluid, change
both the fluid and filter.
0 Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service.
150,000 Miles (240 000 km)
0 Drain, flush and refill cooling system (or every
60 months since last service, whichever occurs first).
See
Engine Coolant on page 5-24 for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.
An Emission Control Service.
0 Inspect engine accessory drive belt. An Emission
Control Service.
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Part C: Periodic Maintenance
Inspections
Listed in this part are inspections and services which
should be performed at least twice a year (for instance,
each spring and fall).
You should let your dealer’s
service department or other qualified service center do
these jobs. Make sure any necessary repairs are
completed at once.
Proper procedures to perform these services may be
found in a service manual. See
Service Publications
Ordering lnformation on page
7- 10.
Steering and Suspension Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system. Look for broken, damaged,
missing or out-of-position parts as well as open seams,
holes, loose connections or other conditions which
could cause a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. See
Engine Exhaust
on page
2-26.
Fuel System Inspection
Inspect the complete fuel system for damage or leaks.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they
are cracked, swollen or deteriorated. Inspect
all pipes,
fittings and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser.
To help ensure proper operation, a pressure test of
the cooling system and pressure cap is recommended
at least once a year.
6-1 4