2020 GMC SIERRA coolant

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 333
1. Remote Negative (–) Location.See Jump Starting - North
America 0419.
2. Positive (+) Terminal (Under Cover). See Jump Starting -
North America 0419.
3. Battery - North America 0358.
4. Engine Compartment Fuse
Block 0371.
5. Engine Cooling Fans (Out of View). See Cooling System
0 346. 6. Engine Oil Fill Cap. See
“When
to Add Engine Oil” under
Engine Oil 0339.
7. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0339.
8. Coolant Surge Tank and Pressure Cap. See Cooling
System 0346.
9. Engine Air Cleaner/Filter 0344.
10. Brake Fluid Reservoir. See Brake Fluid 0357.
11. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 354.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 335
1. Remote Negative (–) Location.See Jump Starting - North
America 0419.
2. Positive (+) Terminal (Under Cover). See Jump Starting -
North America 0419.
3. Battery - North America 0358.
4. Engine Compartment Fuse
Block 0371.
5. Engine Cooling Fans (Out of View). See Cooling System
0 346.
6. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0339. 7. Engine Oil Fill Cap. See
“When
to Add Engine Oil” under
Engine Oil 0339.
8. Coolant Surge Tank and Pressure Cap. See Cooling
System 0346.
9. Engine Air Cleaner/Filter 0344.
10. Brake Fluid Reservoir. See Brake Fluid 0357.
11. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 354.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 337
1. Remote Negative (–) Location.See Jump Starting - North
America 0419.
2. Positive (+) Terminal (Under Cover). See Jump Starting -
North America 0419.
3. Battery - North America 0358.
4. Engine Compartment Fuse
Block 0371.
5. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0339.
6. Engine Cooling Fans (Out of View). See Cooling System
0 346. 7. Engine Oil Fill Cap. See
“When
to Add Engine Oil” under
Engine Oil 0339.
8. Coolant Surge Tank and Pressure Cap. See Cooling
System 0346.
9. Engine Air Cleaner/Filter 0344.
10. Brake Fluid Reservoir. See Brake Fluid 0357.
11. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 354.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 339
1. Remote Negative (–) Location.See Jump Starting - North
America 0419.
2. Positive (+) Terminal (Under Cover). See Jump Starting -
North America 0419.
3. Battery - North America 0358.
4. Engine Air Cleaner/Filter 0344.
5. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0339.
6. Engine Cooling Fan (Out of View). See Cooling System
0 346.
7. Power Steering Fluid Reservoir. See Power Steering
Fluid 0354.
8. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil 0339.
9. Auxiliary Battery. Battery -
North America 0358.
10. Brake Fluid Reservoir. See Brake Fluid 0357.
11. Engine Compartment Fuse
Block 0371. 12. Coolant Surge Tank and
Pressure Cap. See Cooling
System 0346.
13. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 354.
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
Engine Oil
For diesel engine vehicles, see
“Engine Oil” in the Duramax diesel
supplement.
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
. Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section. .
Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0341.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially
prior to a long trip. The engine oil
dipstick handle is a loop. See
Engine Compartment Overview
0332 for the location.
{Warning
The engine oil dipstick handle
may be hot; it could burn you.
Use a towel or glove to touch the
dipstick handle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
346 Vehicle Care
Caution
If the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always
have the air cleaner/filter in place
when driving.
Cooling System
If the vehicle has the Duramax
diesel engine, see the Duramax
diesel supplement.
The cooling system allows the
engine to maintain the correct
working temperature.
2.7L L4 Engine (L3B)
4.3L V6 Engine (LV3)
5.3L V8 Engine (L84) Shown, 5.3LV8 Engine (L82) and 6.2LV8 Engine (L87) Similar
1. Engine Electric Cooling Fans (Out of View)
2. 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 347
6.6L V8 Engine (L8T)
1. Engine Cooling Fan (Outof View)
2. Coolant Surge Tank and Pressure Cap
{Warning
Do not touch heater, radiator, a/c
pipes or 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
(Continued)
Warning (Continued)
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 is designed to
remain in the vehicle for 5 years or
240 000 km (150,000 mi), whichever
occurs first.
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,
seeEngine Overheating 0351.
What to Use
{Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
(Continued)
Warning (Continued)
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. 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
348 Vehicle Care
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 coolant surge tank is in the
engine compartment on the driver
side of the vehicle. See Engine
Compartment Overview 0332.
The vehicle must be on a level
surface when checking the coolant
level.
All Engines Except 6.6L V8 (L8T) Engine
6.6L V8 (L8T) Engine Only
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, wait until it cools down. The
coolant level should be at or above
the indicated mark. If it is not, there
may be a leak in the cooling
system.
If coolant is visible but the coolant
level is not at or above the indicated
mark, see the following sections on
how to add coolant to the coolant
surge tank following.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 349
Automatic Coolant Service Fill
Instructions (L3B Engine)
See 3.0L Duramax Diesel
supplement for the diesel engine
procedure.
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. Set the ignition to Service or Accessory Mode. See Ignition
Positions (Keyless Access)
0 208 or
Ignition Positions (Key Access)
0 210.
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 Electronic 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
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 3–6. The fill and air
removal process will run for
approximately 10 minutes.
How to Add Coolant to the
Coolant Surge Tank for
Gasoline Engines Except L3B
If the vehicle has a diesel engine,
see “Cooling System” in the
Duramax diesel supplement for the
proper coolant fill procedure.
{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
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
(Continued)