2002 GMC ENVOY Radiator hoses

5-11
When the engine is
cold, the coolant
level should be at
least up to the FULL
COLD mark. If it isn't,
you may have a leak at
the pressure cap or in
the radiator hoses,
heater hoses, radiator,
water pump or
somewhere else in
the cooling system.
CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don't touch them.
If you do, you can be burned.
Don't run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
If there seems to be no leak, start the engine again. See if
the engine cooling fan speed increases when idle speed is
doubled by pushing the accelerator pedal down. If it
doesn't, your vehicle needs service. Turn off the engine.
NOTICE:
Engine damage from running your engine
without coolant isn't covered by your warranty.
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.

Scheduled Maintenance
7-14
100,000 Miles (166 000 km)

Replace spark plugs.
An Emission Control Service.

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.
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.
Automatic Transfer Case Only: Change transfer case fluid.
150,000 Miles (240 000 km)
Drain, flush and refill cooling system (or every 60 months since last service,
whichever occurs first). See ªEngine Coolantº in the Index 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.
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

7-20
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 ªService and Owner
Publicationsº in the Index.
Steering, Suspension and Front Drive Axle
Boot and Seal 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. Clean and then inspect the drive
axle boot seals for damage, tears or leakage. Replace
seals if necessary.
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 ªEngine Exhaustº
in the Index.
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.