cooling CHEVROLET BLAZER 2021 User Guide

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
268 Vehicle Care
2.5L L4 Engine
1. Engine Cooling Fan (Out of View)
2. Engine Coolant Surge Tank andPressure Cap
3.6L V6 Engine
1. Engine Cooling Fan (Out of View)
2. Engine Coolant Surge Tank andPressure Cap
{Warning
An underhood electric fan can start up
even when the engine is not running and
can cause injury. Keep hands, clothing,
and tools away from any underhood
electric fan.
{Warning
Do not touch heater or radiator hoses,
or other engine parts. They can be very
hot and can burn you. Do not run the
engine if there is a leak; all coolant could
leak out. That could cause an engine fire
and can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the vehicle is filled
with DEX-COOL engine coolant. This coolant
needs to be checked and replaced at
appropriate intervals. See Maintenance
Schedule 0332.
The following explains the cooling system
and how to check and add coolant when it
is low. If there is a problem with engine
overheating, see Engine Overheating 0271.
What to Use
{Warning
Do not touch heater or radiator hoses,
or other engine parts. They can be very
hot and can burn you. Do not run the
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 269
Warning (Continued)
engine if there is a leak; all coolant could
leak out. That could cause an engine fire
and can burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant. This mixture:
.Gives freezing protection down to −37 °C
(−34 °F), outside temperature.
.Gives boiling protection up to 129 °C
(265 °F), engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Caution
Do not use anything other than a mix of
DEX-COOL coolant that meets GM
Standard GMW3420 and clean, drinkable
water. Anything else can cause damage
to the engine cooling system and the
vehicle, which would not be covered by
the vehicle warranty. Never dispose of engine coolant by putting
it in the trash, or by pouring it on the
ground or into sewers, streams, or bodies of
water. Have the coolant changed by an
authorized service center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface when
checking the coolant level.
Check to see if coolant is visible in the
coolant surge tank. If the coolant inside the
coolant surge tank is boiling, do not do
anything else until it cools down. See
Engine
Overheating 0271. The coolant surge tank is in the engine
compartment on the driver side of the
vehicle. See
Engine Compartment Overview
0 257.
How to Add Coolant to the Coolant
Surge Tank
{Warning
Spilling coolant on hot engine parts can
burn you. Coolant contains ethylene
glycol and it will burn if the engine parts
are hot enough.
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
270 Vehicle Care
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
the wrong mixture, the engine could get
too hot but there would not be an
overheat warning. The engine could catch
fire and you or others could be burned.
Caution
Failure to follow the specific coolant fill
procedure could cause the engine to
overheat and could cause system
damage. If coolant is not visible in the
surge tank, contact your dealer.
If no problem is found, check to see if
coolant is visible in the coolant surge tank.
If coolant is visible but the coolant level is
not at or above the indicated mark, add a
50/50 mixture of clean, drinkable water and
DEX-COOL coolant. Be sure the cooling
system, including the coolant surge tank
pressure cap, is cool before you do it.
2.5L L4 and 3.6L V6 Engines
1. 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.
Turn the pressure cap slowly
counterclockwise about one-quarter of a
turn. If you hear a hiss, wait for that to
stop. This will allow any pressure still
left to be vented out the discharge hose.
2. Keep turning the pressure cap slowly and remove it.
3. Fill the coolant surge tank with theproper mixture to the indicated
level mark.
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 the indicated
level mark.
5. Replace the pressure cap tightly.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 271
6. Verify coolant level after the engine isshut off and the coolant is cold.
If necessary, repeat coolant fill procedure
Steps 1–6.
If the coolant still is not at the proper
level when the system cools down again,
see your dealer.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.
2.0L L4 Engine Only - Automatic Coolant
Service Fill Instructions
If equipped, this feature assists in filling and
removing air from the cooling system after
service of components or when coolant is
added after being too low.
To activate the fill and air removal process:
1. With a cold system, add coolant to the indicated mark on the surge tank.
2. Replace the cap on the surge tank.
3. Connect the vehicle to a battery charger.
4. Turn the ignition to Service Mode. See Ignition Positions 0200. 5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator
and the brake for two seconds, then
release.
At the end of the cycle, check the coolant
level in the surge tank and add coolant if it
is low. Turn off the vehicle, allow the
Electronic Control Module (ECM) to go to
sleep, about two minutes, and repeat
Steps 4–7.
Listen for pump activation and movement of
the control valves while watching the level
of the coolant in the surge tank. If the tank
empties, turn the ignition off, carefully
remove the surge tank cap, refill to the
indicated mark, and repeat Steps 4–7. The
fill and air removal process will run for
approximately 10 minutes.
Engine Overheating
The vehicle has several indicators to warn of
the engine overheating.
There is an engine coolant temperature
gauge on the instrument cluster. See Engine
Coolant Temperature Gauge 096. The
vehicle may also display a message on the
Driver Information Center (DIC). If the decision is made not to lift the hood
when this warning appears, get service help
right away. See
Roadside Assistance Program
0 352.
If the decision is made to lift the hood,
make sure the vehicle is parked on a level
surface. Then check to see if the engine
cooling fan is running. If the engine is
overheating, the fan should be running. If it
is not, do not continue to run the engine.
Have the vehicle serviced.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
If Steam Is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high (Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
272 Vehicle Care
Warning (Continued)
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam Is Coming from the Engine
Compartment
If an engine overheat warning is displayed
but no steam can be seen or heard, the
problem may not be too serious. Sometimes
the engine can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
If the overheat warning is displayed with no
sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan
speed. Open the windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or N (Neutral), and
let the engine idle. If the engine coolant temperature gauge is
no longer in the overheated area, the
vehicle can be driven. Continue to drive the
vehicle slowly for about 10 minutes. Keep a
safe distance from the vehicle in front. If the
warning does not come back on, continue to
drive normally and have the cooling system
checked for proper fill and function.
If the warning continues, pull over, stop, and
park the vehicle right away.
If there is no sign of steam, idle the engine
for three minutes while parked. If the
warning is still displayed, turn off the
engine until it cools down.
Washer Fluid
What to Use
When windshield washer fluid is needed, be
sure to read the manufacturer's instructions
before use. If operating the vehicle in an
area where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap with the washer symbol on it.
Add washer fluid until the tank is full. See
Engine Compartment Overview
0257 for
reservoir location.
Caution
.Do not use washer fluid that contains
any type of water repellent coating.
This can cause the wiper blades to
chatter or skip.
.Do not use engine coolant (antifreeze)
in the windshield washer. It can
damage the windshield washer system
and paint.
.Do not mix water with ready-to-use
washer fluid. Water can cause the
solution to freeze and damage the
washer fluid tank and other parts of
the washer system.
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 305
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider an
alignment check if there is unusual tire wear
or the vehicle is significantly pulling to one
side or the other. Some slight pull to the
left or right, depending on the crown of the
road and/or other road surface variations
such as troughs or ruts, is normal. If the
vehicle is vibrating when driving on a
smooth road, the tires and wheels may
need to be rebalanced. See your dealer for
proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked,
or badly rusted or corroded. If wheel nuts
keep coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If the
wheel leaks air, replace it. Some aluminum
wheels can be repaired. See your dealer if
any of these conditions exist.Your dealer will know the kind of wheel that
is needed.
Each new wheel should have the same
load-carrying capacity, diameter, width,
offset, and be mounted the same way as
the one it replaces.
Replace wheels, wheel bolts, wheel nuts,
or Tire Pressure Monitor System (TPMS)
sensors with new GM original equipment
parts.
{Warning
Using the wrong replacement wheels,
wheel bolts, or wheel nuts can be
dangerous. It could affect the braking and
handling of the vehicle. Tires can lose air,
and cause loss of control, causing a crash.
Always use the correct wheel, wheel
bolts, and wheel nuts for replacement.
Caution
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.
Used Replacement Wheels
{Warning
Replacing a wheel with a used one is
dangerous. How it has been used or how
far it has been driven may be unknown.
It could fail suddenly and cause a crash.
When replacing wheels, use a new GM
original equipment wheel.
Tire Chains
{Warning
If the vehicle has 235/55R20 or 265/45R21
size tires, do not use tire chains. There is
not enough clearance. Tire chains used on
a vehicle without the proper amount of
clearance can cause damage to the
brakes, suspension, or other vehicle parts.
The area damaged by the tire chains
could cause loss of control and a crash.
Use another type of traction device only
if its manufacturer recommends it for the
vehicle's tire size combination and road
conditions. Follow that manufacturer's
instructions. To avoid vehicle damage,
drive slow and readjust or remove the
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Service and Maintenance 333
Air Conditioning Desiccant (Replace Every
Seven Years)
The air conditioning system requires
maintenance every seven years. This service
requires replacement of the desiccant to
help the longevity and efficient operation of
the air conditioning system. This service can
be complex. See your dealer.
Tire Rotation and Required Services
Every 12 000 km/7,500 mi
Rotate the tires, if recommended for the
vehicle, and perform the following services.
SeeTire Rotation 0300.
.Check engine oil level and oil
life percentage. If needed, change engine
oil and filter, and reset oil life system.
See Engine Oil 0262 and
Engine Oil Life System 0264.
.Check the air filter life percentage.
If necessary, replace the engine air filter
and reset the engine air filter life system.
See Engine Air Filter Life System 0265.
.Check engine coolant level. See Cooling
System 0267.
.Check windshield washer fluid level. See
Washer Fluid 0272.
.Check tire inflation pressures. See Tire
Pressure 0294.
.Inspect tire wear. See Tire Inspection
0 300.
.Visually check for fluid leaks.
.Inspect brake system. See Exterior Care
0 323.
.Visually inspect steering, suspension, and
chassis components for damage, including
cracks or tears in the rubber boots, loose
or missing parts, or signs of wear at least
once a year. See Exterior Care0323.
.Inspect power steering for proper
electrical connections, binding, cracks,
chafing, etc.
.Visually inspect halfshafts and drive
shafts for excessive wear, lubricant leaks,
and/or damage including: tube dents or
cracks, constant velocity joint or universal
joint looseness, cracked or missing boots,
loose or missing boot clamps, center
bearing excessive looseness, loose or
missing fasteners, and axle seal leaks.
.Check restraint system components. See
Safety System Check 049.
.Visually inspect the fuel system, including
the evaporative (EVAP) system, for
damage or leaks. Visually check all fuel pipes, vapor lines, and hoses for proper
attachment, connection, routing, and
condition.
.Visually inspect exhaust system and
nearby heat shields for loose or damaged
parts.
.Lubricate body components. See
Exterior
Care 0323.
.Check automatic transmission shift lock
control function. See Automatic
Transmission Shift Lock Control Function
Check 0275.
.Check parking brake and automatic
transmission park mechanism. See Park
Brake and P (Park) Mechanism Check
0 275.
.Check accelerator pedal for damage, high
effort, or binding. Replace if needed.
.Visually inspect gas strut for signs of
wear, cracks, or other damage. Check the
hold open ability of the strut. If the hold
open ability is low, service the gas strut.
See Gas Strut(s) 0277.
.Check tire sealant expiration date,
if equipped. See Tire Sealant and
Compressor Kit 0307.
.Inspect sunroof track and seal,
if equipped. See Sunroof031.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
334 Service and Maintenance
Maintenance Schedule Additional
Required Services - Normal12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi 60 000 km/37,500 mi
72 000 km/45,000 mi84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi 120 000 km/75,000 mi 132 000 km/82,500 mi
144 000 km/90,000 mi 156 000 km/97,500 mi
168 000 km/105,000 mi 180 000 km/112,500 mi
192 000 km/120,000 mi 204 000 km/127,500 mi 216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires and perform Required Services. Check engine oil
level and oil life percentage. Change engine oil and filter,
if needed.
Check engine air filter life percentage and status. Change
engine air filter, if needed. (1)
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
Replace spark plugs. (2.0L engine only.) Inspect spark plug
wires and/or boots.@ @
Replace spark plugs. (except 2.0L engine.) Inspect spark plug
wires and/or boots.@
Change rear axle fluid, if equipped with AWD. (3)@
Drain and fill engine cooling system. (4)@
Visually inspect accessory drive belts. (5)@
Replace brake fluid. (6)
Replace front and rear wiper blades. (7)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas struts. (8)@ @
Replace air conditioning desiccant. (9)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Service and Maintenance 335
Footnotes—Maintenance Schedule
Additional Required Services - Normal
(1) Or every four years, whichever comes
first. If driving in dusty conditions, inspect
the filter at each oil change or more often
as needed. See Engine Air Cleaner/Filter
0 265.
(2) Or every two years, whichever comes
first. More frequent passenger compartment
air filter replacement may be needed if
driving in areas with heavy traffic, poor air
quality, high dust levels, or environmental
allergens. Passenger compartment air filter
replacement may also be needed if there is
reduced airflow, window fogging, or odors.
Your GM dealer can help determine when to
replace the filter. (3)
Do not directly power wash the transfer
case and/or front/rear axle output seals.
High pressure water can overcome the seals
and contaminate the transfer case fluid.
Contaminated fluid will decrease the life of
the transfer case and/or axles and should be
replaced.
(4) Or every five years, whichever comes
first. See Cooling System 0267.
(5) Or every 10 years, whichever comes first.
Inspect for fraying, excessive cracking,
or damage; replace, if needed. (6)
Replace brake fluid every five years. See
Brake Fluid 0273.
(7) Or every 12 months, whichever comes
first. See Wiper Blade Replacement 0276.
(8) Or every 10 years, whichever comes first.
See Gas Strut(s) 0277.
(9) Replace air conditioning desiccant every
seven years.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
336 Service and Maintenance
Maintenance Schedule Additional
Required Services - Severe12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi 60 000 km/37,500 mi
72 000 km/45,000 mi84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi 120 000 km/75,000 mi 132 000 km/82,500 mi
144 000 km/90,000 mi 156 000 km/97,500 mi
168 000 km/105,000 mi 180 000 km/112,500 mi
192 000 km/120,000 mi 204 000 km/127,500 mi 216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires and perform Required Services. Check engine oil
level and oil life percentage. Change engine oil and filter,
if needed.
Check engine air filter life percentage and status. Change
engine air filter, if needed. (1)
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
Change automatic transmission fluid.@ @@
Replace spark plugs. (2.0L engine only.) Inspect spark plug
wires and/or boots.@ @
Replace spark plugs. (except 2.0L engine.) Inspect spark plug
wires and/or boots.@
Change rear axle fluid, if equipped with AWD. (3)@ @
Drain and fill engine cooling system. (4)@
Visually inspect accessory drive belts. (5)@
Replace brake fluid. (6)
Replace front and rear wiper blades. (7)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas struts. (8)@@
Replace air conditioning desiccant. (9)