engine overheat GMC ACADIA 2020 User Guide

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Driving and Operating 197
Shifting Into Park
{Warning
It can be dangerous to get out of
the vehicle if the vehicle is not in
P (Park) with the parking brake
set. The vehicle can roll. If you
have left the engine running, the
vehicle can move suddenly. You
or others could be injured. To be
sure the vehicle will not move,
even when you are on fairly level
ground, use the steps that follow.
If you are pulling a trailer, see
Driving Characteristics and
Towing Tips0246.
To shift into P (Park): 1. Hold the brake pedal down and set the parking brake. See
Electric Parking Brake 0207.
2. Press P (Park).
3. Turn the ignition off.
Leaving the Vehicle with the
Engine Running
{Warning
It can be dangerous to leave the
vehicle with the engine running.
It could overheat and catch fire.
It is dangerous to get out of the
vehicle if the vehicle is not in
P (Park) with the parking brake
set. The vehicle can roll.
Do not leave the vehicle when the
engine is running. If you have left
the engine running, the vehicle
can move suddenly. You or others
could be injured. To be sure the
vehicle will not move, even when
you are on fairly level ground,
always set the parking brake and
shift the vehicle to P (Park). See
Shifting Into Park 0197. If you
are towing a trailer, see Driving
Characteristics and Towing Tips
0 246. If you have to leave the vehicle with
the engine running, the vehicle must
be in P (Park) with the parking
brake set.
Confirm that the vehicle is in
P (Park).
Torque Lock
Torque lock is when the weight of
the vehicle puts too much force on
the parking pawl in the
transmission. This happens when
parking on a hill and shifting the
transmission into P (Park) is not
done properly and then it is difficult
to shift out of P (Park). To prevent
torque lock, set the parking brake
and then shift into P (Park). To find
out how, see
“Shifting Into Park”
listed previously.
On certain steep grades, the
transmission will automatically set
the parking brake to prevent
torque lock.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Driving and Operating 249
The vehicle can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts too
often under heavy loads and/or hilly
conditions.
When towing at higher altitudes,
engine coolant will boil at a lower
temperature than at lower altitudes.
If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle could show signs similar to
engine overheating. To avoid this,
let the engine run, preferably on
level ground, with the transmission
in P (Park) for a few minutes before
turning the engine off. If the
overheat warning comes on, see
Engine Overheating0279.
Viewing Systems
If equipped, the viewing systems on
the vehicle can improve visibility
while hitching, backing, and driving
with a trailer. See Driver Assistance
Systems 0225 and
Assistance Systems for Parking or
Backing 0227.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and
trailer on a level surface when
possible.
When parking your vehicle and your
trailer on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, gradually release the
brake pedal to allow the chocks
to absorb the load of the trailer.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal:
.Start the engine.
. Shift into a gear.
. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when used to tow trailers. See
Maintenance Schedule 0353. It is
especially important to check the
engine oil, axle lubricant, belts,
cooling system, and brake system
before and during each trip.
Check periodically that all nuts and
bolts on the trailer hitch are tight.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
250 Driving and Operating
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. SeeEngine Overheating
0 279.
Trailer Towing
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer
for important information about
towing a trailer with the vehicle.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring
the weight, speed, altitude, road
grades, outside temperature,
dimensions of the front of the trailer,
and how frequently the vehicle is
used to tow a trailer.
Trailer Weight Ratings
When towing a trailer, the weight of
the loaded vehicle and trailer must
be within the weight ratings for the
vehicle.
. GCWR: Gross Combined Weight
Rating
. GVWR: Gross Vehicle Weight
Rating
. Maximum Trailer Weight Rating
. Maximum Trailer Tongue Weight The only way to be sure the weight
is not exceeding any of these
ratings is to weigh the tow vehicle
and trailer combination, fully loaded
for the trip, getting individual
weights for each of these items.
{Warning
You and others could be seriously
injured or killed if the trailer is too
heavy or the trailer brakes are
inadequate for the load. The
vehicle may be damaged, and the
repairs would not be covered by
the vehicle warranty.
Only tow a trailer if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 259
Vehicle Care
General Information
General Information . . . . . . . . . . 260
California Proposition65 Warning . . . . . . . . . . . . . . . . . 260
California Perchlorate Materials Requirements . . . . . 261
Accessories and Modifications . . . . . . . . . . . . . . . . 261
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 261
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 262
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 264
Engine Oil . . . . . . . . . . . . . . . . . . . . 269
Engine Oil Life System . . . . . . . 271
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 272
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 273
Engine Air Cleaner/Filter . . . . . . 273
Cooling System . . . . . . . . . . . . . . 275
Engine Overheating . . . . . . . . . . 279
Washer Fluid . . . . . . . . . . . . . . . . . 281
Brakes . . . . . . . . . . . . . . . . . . . . . . . 281
Brake Fluid . . . . . . . . . . . . . . . . . . . 282 Battery - North America . . . . . . 283
All-Wheel Drive . . . . . . . . . . . . . . . 284
Starter Switch Check . . . . . . . . . 284
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 285
Wiper Blade Replacement . . . . 285
Windshield Replacement . . . . . 286
Gas Strut(s) . . . . . . . . . . . . . . . . . . 286
Headlamp Aiming
Front Headlamp Aiming . . . . . . 288
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 288
Halogen Bulbs . . . . . . . . . . . . . . . . 288
LED Lighting . . . . . . . . . . . . . . . . . 288
Electrical System
Electrical System Overload . . . 289
Fuses and Circuit Breakers . . . 289
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 290
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 293
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 295
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 297
All-Season Tires . . . . . . . . . . . . . . 298
Winter Tires . . . . . . . . . . . . . . . . . . 299
Summer Tires . . . . . . . . . . . . . . . . 299 Tire Sidewall Labeling . . . . . . . . 300
Tire Designations . . . . . . . . . . . . . 302
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 302
Tire Pressure . . . . . . . . . . . . . . . . . 305
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 306
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 307
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 308
Tire Inspection . . . . . . . . . . . . . . . . 312
Tire Rotation . . . . . . . . . . . . . . . . . 312
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 313
Buying New Tires . . . . . . . . . . . . . 314
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 315
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 316
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 317
Wheel Replacement . . . . . . . . . . 318
Tire Chains . . . . . . . . . . . . . . . . . . . 318
If a Tire Goes Flat . . . . . . . . . . . . 319
Tire Sealant and Compressor Kit . . . . . . . . . . . . . 321
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . 327
Tire Changing . . . . . . . . . . . . . . . . 328

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
276 Vehicle Care
3.6L V6 Engine
1. Engine Cooling Fan (Outof View)
2. Engine Coolant Surge Tank and Pressure 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 0353.
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 0279.
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 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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 277
.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, 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 0279.
The coolant surge tank is located in
the engine compartment on the
driver side of the vehicle. See
Engine Compartment Overview
0 264.
{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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
278 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.
How to Add Coolant to the
Coolant Surge Tank (2.5L and
3.6L Engines Only)
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 withthe proper 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

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 279
mixture to the coolant surge
tank until the level reaches the
indicated level mark.
5. Replace the pressure cap tightly.
6. Verify coolant level after the engine is shut 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.
Automatic Coolant Service Fill
(2.0L Engine Only)
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, disconnect the vent line from the port near
the cap on the surge tank. Add
coolant to the indicated mark
on the surge tank.
2. Reconnect the vent line to the surge tank and replace the cap
on the surge tank.
3. Connect the vehicle to a battery charger.
4. Put the vehicle in Service Mode. See Ignition Positions
0 190.
5. Turn off the air conditioning.
6. Set the parking brake. 7. At the same time, press the
accelerator and the brake for
automatic transmission
vehicles 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 Engine Control
Module (ECM) to go to sleep, about
two minutes, and repeat steps 3-7.
Listen for pump activation and
movement of the control valves
while watching the level of the tank.
If the tank empties, turn the ignition
off, carefully remove the surge tank
cap, refill to the indicated mark and
repeat steps 3-6. 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 0123.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
280 Vehicle Care
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
0374.
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 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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13687875) - 2020 - CRC - 10/28/19
396 Index
Driver InformationCenter (DIC) . . . . . . . . . . . . . 137, 139
Driver Mode Control . . . . . . . . . . . . 212
Driving Assistance Systems . . . . . . . . . . 231
Better Fuel Economy . . . . . . . . . 174
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . 246
Defensive . . . . . . . . . . . . . . . . . . . . . 175
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . 175
Hill and Mountain Roads . . . . . . 183
If the Vehicle is Stuck . . . . . . . . . 185
Loss of Control . . . . . . . . . . . . . . . 177
Off-Road . . . . . . . . . . . . . . . . . . . . . 178
Off-Road Recovery . . . . . . . . . . . 177
Vehicle Load Limits . . . . . . . . . . . 186
Wet Roads . . . . . . . . . . . . . . . . . . . 182
Winter . . . . . . . . . . . . . . . . . . . . . . . . 184
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . 165
E
Electric Brake Boost . . . . . . . . . . . . 206
Electric Parking Brake . . . . . . . . . . 207
Electric Parking Brake Light . . . . 130
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . . 258 Electrical System
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 290
Fuses and Circuit Breakers . . . 289
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 293
Overload . . . . . . . . . . . . . . . . . . . . . 289
Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 295
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . 385
Engine Air Cleaner/Filter . . . . . . . . . . . . . 273
Check Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . 127
Compartment Overview . . . . . . . 264
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 123
Coolant Temperature Warning Light . . . . . . . . . . . . . . . 133
Cooling System . . . . . . . . . . . . . . . 275
Drive Belt Routing . . . . . . . . . . . . 369
Exhaust . . . . . . . . . . . . . . . . . . . . . . 200
Heater . . . . . . . . . . . . . . . . . . . . . . . . 194
Oil Life System . . . . . . . . . . . . . . . 271
Oil Pressure Light . . . . . . . . . . . . 134
Overheating . . . . . . . . . . . . . . . . . . 279
Power Messages . . . . . . . . . . . . . 146 Engine (cont'd)
Running While Parked . . . . . . . . 201
Starting . . . . . . . . . . . . . . . . . . . . . . . 192
Engine Air Filter Life System . . . . 273
Engine Oil Temperature Gauge . . . . . . . . . . 123
Entry Lighting . . . . . . . . . . . . . . . . . . . 161
Equipment, Towing . . . . . . . . . . . . . 253
Event Data Recorders . . . . . . . . . . 382
Exit Lighting . . . . . . . . . . . . . . . . . . . . 161
Extended Parking . . . . . . . . . . . . . . . 200
Extender, Seat Belt . . . . . . . . . . . . . . 63
Exterior Lamp Controls . . . . . . . . . 155
Exterior Lamps Off Reminder . . . 157
Exterior Lighting Battery Saver . . . . . . . . . . . . . . . . . . . . . . . . . 163
F
Filter,
Engine Air Cleaner . . . . . . . . . . . 273
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 157
Flashers, Hazard Warning . . . . . . 159
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 319 Changing . . . . . . . . . . . . . . . . . . . . . 328
Floor Mats . . . . . . . . . . . . . . . . . . . . . . 350
Fluid Automatic Transmission . . . . . . 272
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 282