
GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
264 Vehicle Care
Engine oil system flushes are not
recommended and could cause engine
damage not covered by the vehicle
warranty.
What to Do with Used Oil
Used engine oil contains certain elements
that can be unhealthy for your skin and
could even cause cancer. Do not let used oil
stay on your skin for very long. Clean your
skin and nails with soap and water, or a
good hand cleaner. Wash or properly
dispose of clothing or rags containing used
engine oil. See the manufacturer's warnings
about the use and disposal of oil products.
Used oil can be a threat to the environment.
If you change your own oil, be sure to drain
all the oil from the filter before disposal.
Never dispose of oil by putting it in the
trash or pouring it on the ground, into
sewers, or into streams or bodies of water.
Recycle it by taking it to a place that
collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that
indicates when to change the engine oil and
filter. This is based on a combination offactors which include engine revolutions,
engine temperature, and miles driven. Based
on driving conditions, the mileage at which
an oil change is indicated can vary
considerably. For the oil life system to work
properly, the system must be reset every
time the oil is changed.
When the system has calculated that oil life
has been diminished, it indicates that an oil
change is necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the oil as
soon as possible within the next 1 000 km
(600 mi). It is possible that, if driving under
the best conditions, the oil life system may
indicate that an oil change is not necessary
for up to a year. The engine oil and filter
must be changed at least once a year and,
at this time, the system must be reset. Your
dealer has trained service people who will
perform this work and reset the system.
It is also important to check the oil regularly
over the course of an oil drain interval and
keep it at the proper level.
If the system is ever reset accidentally, the
oil must be changed at 5 000 km (3,000 mi)
since the last oil change. Remember to reset
the oil life system whenever the oil is
changed.
How to Reset the Engine Oil Life System
Reset the system whenever the engine oil is
changed so that the system can calculate
the next engine oil change. To reset the
system:
1. Display REMAINING OIL LIFE on the DIC menu. See Driver Information Center
(DIC) (Base and Midlevel) 0100 or
Driver Information Center (DIC) (Uplevel)
0 105.
2. Press and hold
Vfor several seconds
while the Oil Life display is active to
reset the Oil Life system.
3. REMAINING OIL LIFE 100% will be displayed when the oil life system is
successfully reset.
The oil life system can also be reset as
follows: 1. Place the ignition in Service Mode. See Ignition Positions 0199.
2. Display REMAINING OIL LIFE on the DIC menu. See Driver Information Center
(DIC) (Base and Midlevel) 0100 or
Driver Information Center (DIC) (Uplevel)
0 105.
3. Fully press and release the accelerator pedal three times within five seconds.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
268 Vehicle Care
Engine Coolant
The engine cooling system in the vehicle is
filled with DEX-COOL engine coolant mixture.
This coolant needs to be checked and
changed at appropriate levels. See
Recommended Fluids and Lubricants0339
and
Maintenance Schedule 0331.
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 0270.
What to Use
{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.
Use a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant. If using this
mixture, nothing else needs to be added.
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, pouring it on the ground,
or pouring 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. If coolant
is visible but the coolant level mark is not
visible, add a 50/50 mixture of clean,
drinkable water and DEX-COOL coolant at
the coolant surge tank to the top rib on the
middle of the tank, but be sure the cooling
system is cool before this is done. See
Engine Overheating 0270.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/-
Mexico-14420055) - 2021 - CRC - 11/13/20
368 Index
Driving (cont'd)Better Fuel Economy . . . . . . . . . . . . . . . . . . . 187
Characteristics and Towing Tips . . . . . . . . 249
Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
Hill and Mountain Roads . . . . . . . . . . . . . . 194
If the Vehicle is Stuck . . . . . . . . . . . . . . . . . 195
Impaired . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . 190
Off-Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . 189
Vehicle Load Limits . . . . . . . . . . . . . . . . . . . . 196
Wet Roads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Driving the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . .2
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
E
Electric Parking Brake . . . . . . . . . . . . . . . . . . . . . 212
Electric Parking Brake Light . . . . . . . . . . . . . . . 95
Electrical Equipment, Add-On . . . . . . . . . . . . 256
Electrical SystemEngine Compartment Fuse Block . . . . . . . 281
Fuses and Circuit Breakers . . . . . . . . . . . . . 280
Instrument Panel Fuse Block . . . . . . . . . . . 284
Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
Rear Compartment Fuse Block . . . . . . . . . 285 Emergency
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . 265
Check Light (Malfunction Indicator) . . . . . 93
Compartment Overview . . . . . . . . . . . . . . . . 261
Coolant Temperature Gauge . . . . . . . . . . . . 91
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 267
Drive Belt Routing . . . . . . . . . . . . . . . . . . . . . 345
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 264
Oil Pressure Light . . . . . . . . . . . . . . . . . . . . . . . 98
Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Power Messages . . . . . . . . . . . . . . . . . . . . . . . 108
Running While Parked . . . . . . . . . . . . . . . . . 208
Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Engine Air Filter Life System . . . . . . . . . . . . . 265
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Equipment, Towing . . . . . . . . . . . . . . . . . . . . . . 254
Event Data Recorders . . . . . . . . . . . . . . . . . . . . 356
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Extended Parking . . . . . . . . . . . . . . . . . . . . . . . . 207
Extender, Seat Belt . . . . . . . . . . . . . . . . . . . . . . . 46
Exterior Lamp Controls . . . . . . . . . . . . . . . . . . . . 116
Exterior Lighting Battery Saver . . . . . . . . . . . 122
F
Filter, Engine Air Cleaner . . . . . . . . . . . . . . . . . . . . . 265
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Flashers, Hazard Warning . . . . . . . . . . . . . . . . . 119
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Changing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Fluid Automatic Transmission . . . . . . . . . . . . . . . 265
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Folding Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Folding Seatback . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Forward Collision Alert (FCA) System . . . . 237
Frequency Statement Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
Front Fog Lamp
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Front Pedestrian Braking (FPB) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
Front Seats Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Heated and Ventilated . . . . . . . . . . . . . . . . . . 35
Front Turn Signal Lamps . . . . . . . . . . . . . . . . . 278
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247