
GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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220 Driving and Operating
Warning (Continued)
.Do not move the vehicle if someone is
in the path of the trailer. Some parts
of the trailer might be underwater and
not visible to people who are assisting
in launching the boat.
Disconnect the wiring to the trailer before
backing the trailer into the water to prevent
damage to the electrical circuits on the
trailer. Reconnect the wiring to the trailer
after removing the trailer from the water.
If the trailer has electric brakes that can
function when the trailer is submerged, it
might help to leave the electrical trailer
connector attached to maintain trailer brake
functionality while on the boat ramp.
To back the trailer into the water: 1. If equipped, place the vehicle in four-wheel-drive high.
2. Slowly back down the boat ramp until the boat is floating, but no further than
necessary.
3. Press and hold the brake pedal, but do not shift into P (Park) yet.
4. Have someone place chocks under the front wheels of the vehicle. 5. Gradually release the brake pedal to
allow the chocks to absorb the load of
the trailer.
6. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
7. Release the brake pedal.
Pulling the Trailer from the Water
To pull the trailer of the water: 1. Press and hold the brake pedals.
2. Start the engine and shift into gear.
3. Release the parking brake.
4. Let up on the brake pedal.
5. Drive slowly until the tires are clear of the chocks.
6. Stop and have someone pick up and store the chocks.
7. Slowly pull the trailer from the water.
8. Once the vehicle and trailer have been driven from the sloped part of the boat
ramp, the vehicle can be shifted from
four-wheel-drive high. Shift into the drive
mode that is appropriate for the road
conditions.
Caution
If the vehicle tires begin to spin and the
vehicle begins to slide toward the water,
remove your foot from the accelerator
pedal and apply the brake pedal. Seek
help to have the vehicle towed up
the ramp.
Maintenance when Trailer Towing
The vehicle needs service more often when
used to tow trailers. See Maintenance
Schedule 0310. It is especially important to
check the automatic transmission fluid,
engine oil, axle lubricant, belts, cooling
system, and brake system before and during
each trip.
Check periodically to see that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0247.
Trailer Towing
If equipped with a diesel engine, see the
Duramax diesel supplement.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 243
Automatic Transmission Fluid
How to Check Automatic Transmission
Fluid
It is not necessary to check the transmission
fluid level. A transmission fluid leak is the
only reason for fluid loss. If a leak occurs,
take the vehicle to your dealer and have it
repaired as soon as possible.
There is a special procedure for checking and
changing the transmission fluid. Because this
procedure is difficult, this should be done at
your dealer. Contact your dealer for
additional information.
Caution
Use of the incorrect automatic
transmission fluid may damage the
vehicle, and the damage may not be
covered by the vehicle warranty. Always
use the correct automatic transmission
fluid. SeeRecommended Fluids and
Lubricants 0319.
Change the fluid and filter at the intervals
listed in Maintenance Schedule 0310, and
be sure to use the fluid listed in
Recommended Fluids and Lubricants 0319.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the engine
compartment on the passenger side of the
vehicle. See Engine Compartment Overview
0 237.
When to Inspect/Replace the Engine Air
Cleaner/Filter
For intervals on changing and inspecting the
engine air cleaner/filter, see Maintenance
Schedule 0310.
How to Inspect/Replace the Engine Air
Cleaner/Filter
Do not start the engine or have the engine
running with the engine air cleaner/filter
housing open. Before removing the engine
air cleaner/filter, make sure that the engine
air cleaner/filter housing and nearby
components are free of dirt and debris.
Remove the engine air cleaner/filter. Lightly
tap and shake the engine air cleaner/filter
(away from the vehicle), to release loose
dust and dirt. Inspect the engine air cleaner/
filter for damage, and replace if damaged.
Do not clean the engine air cleaner/filter or
components with water or compressed air. To inspect or replace the air cleaner/filter:
2.5L L4 Gas Engine Shown, 2.8L L4 Diesel
Engine Similar
1. Screws
2. Electrical Connector
3. Air Duct Clamp
To inspect or replace the engine air cleaner/
filter:
1. Remove the screws (1) on top of the engine air cleaner/filter housing.
2. Disconnect the electrical connector (2).
3. Disconnect the outlet duct by loosening the air duct clamp (3).

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
Vehicle Care 245
Cooling System
The cooling system allows the engine to
maintain the correct working temperature.
2.5L L4 Gas Engine Shown, 2.8L L4 DieselEngine Similar
1. Coolant Surge Tank and Pressure Cap
2. Engine Cooling Fan (Out of View)
3.6L V6 Engine
1. Coolant Surge Tank and Pressure Cap
2. Engine Cooling Fan (Out of View)
{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 mixture. See
Recommended Fluids and Lubricants 0319
and
Maintenance Schedule 0310.
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 0247.
What to Use
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
(Continued)

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 251
{Warning
If too much brake fluid is added, it can
spill on the engine and burn, if the
engine is hot enough. You or others could
be burned, and the vehicle could be
damaged. Add brake fluid only when
work is done on the brake hydraulic
system.
When the brake fluid falls to a low level,
the brake warning light comes on. See Brake
System Warning Light 089.
Brake fluid absorbs water over time which
degrades the effectiveness of the brake fluid.
Replace brake fluid at the specified intervals
to prevent increased stopping distance. See
Maintenance Schedule 0310.
What to Add
Use only GM approved DOT 3 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants 0319.
{Warning
The wrong or contaminated brake fluid
could result in damage to the brake
system. This could result in the loss of
(Continued)
Warning (Continued)
braking leading to a possible injury.
Always use the proper GM approved
brake fluid.
Caution
If brake fluid is spilled on the vehicle's
painted surfaces, the paint finish can be
damaged. Immediately wash off any
painted surface.
Battery - North America
For diesel engine vehicles, see“Battery”in
the Duramax diesel supplement.
The original equipment battery is
maintenance free. Do not remove the cap
and do not add fluid.
Refer to the replacement number shown on
the original battery label when a new
battery is needed. See Engine Compartment
Overview 0237 for battery location.
{Warning
WARNING: Battery posts, terminals, and
related accessories contain lead and lead
compounds, chemicals known to the
State of California to cause cancer and
birth defects or other reproductive harm.
Batteries also contain other chemicals
known to the State of California to cause
cancer. WASH HANDS AFTER HANDLING.
For more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition 65 Warning 0234
and the back cover.
Vehicle Storage
{Warning
Batteries have acid that can burn you and
gas that can explode. You can be badly
hurt if you are not careful. See Jump
Starting - North America 0294 for tips
on working around a battery without
getting hurt.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
252 Vehicle Care
Infrequent Usage: Remove the black,
negative (−) cable from the battery to keep
the battery from running down.
Extended Storage: Remove the black,
negative (−) cable from the battery or use a
battery trickle charger.
Four-Wheel Drive
Transfer Case
When to Check Lubricant
Refer toMaintenance Schedule 0310 to
determine when to check the lubricant. How to Check Lubricant
Automatic Transfer Case
1. Drain Plug
2. Fill Plug
To get an accurate reading, the vehicle
should be on a level surface.
If the level is below the bottom of the fill
plug (2) hole, located on the transfer case,
some lubricant will need to be added. Add
enough lubricant to raise the level to the
bottom of the fill plug (2) hole. Use care not
to overtighten the plug.When to Change Lubricant
Refer to
Maintenance Schedule 0310 to
determine how often to change the
lubricant.
What to Use
Refer to Recommended Fluids and Lubricants
0 319 to determine what kind of lubricant
to use.
Front Axle
When to Check Lubricant
It is not necessary to regularly check the
front axle fluid unless a leak is suspected or
an unusual noise is heard. A fluid loss could
indicate a problem. Have it inspected and
repaired. This service can be complex. See
your dealer.
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 fluid. Contaminated
fluid will decrease the life of the transfer
case and/or drive axles and should be
replaced.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 255
{Warning
If the gas struts that hold open the hood,
trunk, and/or liftgate fail, you or others
could be seriously injured. Take the
vehicle to your dealer for service
immediately. Visually inspect the gas
struts for signs of wear, cracks, or other
damage periodically. Check to make sure
the hood/trunk/liftgate is held open with
enough force. If struts are failing to hold
the hood/trunk/liftgate, do not operate.
Have the vehicle serviced.
Caution
Do not apply tape or hang any objects
from gas struts. Also do not push down
or pull on gas struts. This may cause
damage to the vehicle.
See Maintenance Schedule 0310.
Hood
Trunk
Liftgate
Headlamp Aiming
Front Headlamp Aiming
Headlamp aim has been preset and should
need no further adjustment.
If the vehicle is damaged in a crash, the
headlamp aim may be affected.
If adjustment to the headlamps is necessary,
see your dealer.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 277
Tire Rotation
Tires should be rotated every 12 000 km
(7,500 mi). SeeMaintenance Schedule
0 310.
Tires are rotated to achieve a more
uniform wear for all tires. The first
rotation is the most important.
Anytime unusual wear is noticed, rotate
the tires as soon as possible, check for
proper tire inflation pressure, and check
for damaged tires or wheels. If the
unusual wear continues after the
rotation, check the wheel alignment.
See When It Is Time for New Tires 0278
and
Wheel Replacement 0281.
Use this rotation pattern when rotating
the tires.
Do not include the spare tire in the tire
rotation.
Adjust the front and rear tires to the
recommended inflation pressure on the
Tire and Loading Information label after
the tires have been rotated. See Tire
Pressure 0272 and
Vehicle Load Limits 0180.
Reset the Tire Pressure Monitor System.
See Tire Pressure Monitor Operation
0 274. Check that all wheel nuts are properly
tightened. See
“Wheel Nut Torque”
under Capacities and Specifications
0 324.
{Warning
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
cause wheel nuts to become loose
over time. The wheel could come off
and cause a crash. When changing a
wheel, remove any rust or dirt from
places where the wheel attaches to
the vehicle. In an emergency, a cloth
or paper towel can be used; however,
use a scraper or wire brush later to
remove all rust or dirt.
Lightly coat the inner diameter of the
wheel hub opening with wheel bearing
grease after a wheel change or tire
rotation to prevent corrosion or rust
build-up.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 291
4. Insert the hoist end (10) through thehole (9) in the rear bumper and onto the
hoist shaft.
Do not use the chiseled end of the wheel
wrench.
5. Raise the tire part way upward. Make sure the retainer is seated in the wheel
opening.
6. Raise the tire fully against the underside of the vehicle by turning the wheel
wrench clockwise until you hear two
clicks or feel it skip twice. You cannot
overtighten the cable.
7. Make sure the tire is stored securely andflush in the radius (2) of the spare tire
support bracket (1). Push, pull, and then try to turn the tire. If the tire moves,
use the wheel wrench to tighten the
cable.
Repeat this tightness check procedure
when checking the spare tire pressure
according to the scheduled maintenance
information or any time the spare tire is
handled due to service of other
components.
Correctly Stored