GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
320 Vehicle Care
.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 coolant surge tank is in the engine
compartment on the driver side of the
vehicle. See Engine Compartment Overview
0 313. 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, 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.
How to Add Coolant to the Coolant
Surge Tank
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 warning. The engine could catch
fire and you or others could be burned.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Vehicle Care 323
normal idle speed for at least five minutes
while the vehicle is parked. If the warning is
still there, turn off the engine and get
everyone out of the vehicle until it
cools down.
If there is no sign of steam, idle the engine
for five minutes while parked. If the warning
is still displayed, turn off the engine until it
cools down.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and
the ENGINE POWER IS REDUCED message
displays, an overheat protection mode which
alternates firing groups of cylinders helps to
prevent engine damage. In this mode, a loss
in power and engine performance will be
noticed. This operating mode allows the
vehicle to be driven to a safe place in an
emergency. Driving extended distances
and/or towing a trailer in the overheat
protection mode should be avoided.
If the engine or transmission detects an
impending hot fluid condition, then the
transmission may force upshifts to limit
temperatures. Downshifts may also be
prevented in this instance. Normal operationmay continue unless the display indicates
there is a hot condition and engine should
be idled.
Caution
After driving in the overheated engine
protection operating mode, the engine oil
will be severely degraded. Any repairs
performed before the engine is cool may
cause engine damage. Allow the engine
to cool before attempting any repair.
Repair the cause of coolant loss, change
the oil, and reset the oil life system. See
Engine Oil
0314.
Engine Fan
If the vehicle has the Duramax diesel
engine, see the Duramax diesel supplement.
The vehicle has a clutched engine cooling
fan. When the clutch is engaged, the fan
spins faster to provide more air to cool the
engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is
not fully engaged. This improves fuel
economy and reduces fan noise. Under
heavy vehicle loading, trailer towing, and/or
high outside temperatures, the fan speed
increases as the clutch more fully engages, so an increase in fan noise may be heard.
This is normal and should not be mistaken
as the transmission slipping or making extra
shifts. It is merely the cooling system
functioning properly. The fan will slow down
when additional cooling is not required and
the clutch partially disengages.
This fan noise may be heard when starting
the engine. It will go away as the fan clutch
partially disengages.
Power Steering Fluid
The power steering fluid reservoir is in the
engine compartment on the driver side of
the vehicle. See
Engine Compartment
Overview 0313 for reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering fluid unless there is a leak
suspected in the system or an unusual noise
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Vehicle Care 339
FusesUsage
6 –
7 ELM 4 –Electronic
Lighting Module 4
8 –
9 –
10 ELM 6 –Electronic
Lighting Module 6
11 BCM 3 –Body Control
Module 3
12 Rear Window Defogger
13 Washer Front
14 –
15 –
16 –
17 IECL 1
19 DC/AC Inverter
20 IECR 2 (LD)/EBCM2 (HD) 21 –
22 IECL 2
24 Fuel Heater (DSL) Fuses
Usage
25 EBCM 1 –Electronic
Brake Control Module 1
26 –
27 Horn
28 Parking Lamp Mirror/ Grill (LD)/Parking Lamp
Left (HD)
29 Parking Lamp Right (HD)
30 ELM 3 –Electronic
Lighting Module 3
31 ELM 1 –Electronic
Lighting Module 1
32 –
33 Not R/C
34 Radars (LD) 37 MISC IP Headliner Ignition
38 Seat Fan Ignition
39 Trailer Ignition Module
40 Misc Ignition 41 Trailer Parking Lamp Fuses
Usage
42 Tail Lamp Left (HD)
44 DEFC/ICCM Ignition (LD/ HD)/FTZM Ignition (HD)
45 Secondary Axle Motor
46 Engine Control Module Ignition
47 –
48 –
49 Transmission Auxiliary Oil Pump (LD)
50 A/C Clutch 51 Transfer Case Control Module
52 Front Wiper
53 Center High-Mounted Stop Lamp
54 Tail Lamp Right (HD) 55 Trailer Back-up Lamp
56 SADS (LD)/Fuel Tank Zone Module 2 (HD)
57 TTPM/SBZA
58 Starter Motor (LD)
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Vehicle Care 371
7. Remove all the wheel nuts and take offthe flat tire.
{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.
8. Remove any rust or dirt from the wheel bolts, mounting surfaces, and spare
wheel.
9. Install the spare tire.
{Warning
Never use oil or grease on bolts or nuts
because the nuts might come loose. The
vehicle's wheel could fall off, causing a
crash.
10. Put the wheel nuts back on with the rounded end of the nuts toward the
wheel. 11. Tighten each wheel nut by hand. Then
use the wheel wrench to tighten the
nuts until the wheel is held against
the hub.
12. Turn the wheel wrench counterclockwise to lower the vehicle. Lower the jack
completely.
{Warning
If wheel studs are damaged, they can
break. If all the studs on a wheel broke,
the wheel could come off and cause a
crash. If any stud is damaged because of
a loose-running wheel, it could be that all
of the studs are damaged. To be sure,
replace all studs on the wheel. If the stud
holes in a wheel have become larger, the
wheel could collapse in operation. Replace
any wheel if its stud holes have become
larger or distorted in any way. Inspect
hubs and hub‐piloted wheels for damage.
Because of loose running wheels, piloting
pad damage may occur and require
replacement of the entire hub, for proper
centering of the wheels. When replacing
studs, hubs, wheel nuts or wheels, be
sure to use GM original equipment parts.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
384 Vehicle Care
Cleaning Underhood Components
Caution
Do not power wash any component
under the hood that has this
e
symbol.
This could cause damage that would not
be covered by the vehicle warranty.
Solvents or aggressive cleaners may harm
underhood components. The usages of these
chemicals should be avoided.
Recommend water only.
A pressure washer may be used, but care
must be utilized. The following criteria must
be followed:
.Water pressure must be kept below
14 000 KPa (2,000 PSI).
.Water temperature must be below 80 °C
(180 °F).
.Spray nozzle with a 40 degree wide angle
spray pattern or wider must be used.
.Nozzle must be kept at least 30 cm (1 ft)
away from all surfaces. Automatic Car Wash
Caution
Some automatic car washes can cause
damage to the vehicle, wheels and
ground effects. Automatic car washes are
not recommended, due to lack of
clearance for the undercarriage and/or
wide rear tires and wheels.
Caution
Automatic car washes can cause damage
to the vehicle, wheels, ground effects,
and convertible top (if equipped).
Do not use automatic car washes due to
lack of clearance for the undercarriage,
wide rear tires, and wheels.
If using an automatic car wash, follow with
the car wash instructions. The windshield
wiper and rear window wiper, if equipped,
must be turned off. Remove any accessories
that may be damaged or interfere with the
car wash equipment.
See Power Assist Steps 031 for cleaning
information. Rinse the vehicle well, before washing and
after, to remove all cleaning agents
completely. If they are allowed to dry on
the surface, they could stain.
Dry the finish with a soft, clean chamois or
an all-cotton towel to avoid surface
scratches and water spotting.
Finish Care
Application of aftermarket clearcoat
sealant/wax materials is not recommended.
If painted surfaces are damaged, see your
dealer to have the damage assessed and
repaired. Foreign materials such as calcium
chloride and other salts, ice melting agents,
road oil and tar, tree sap, bird droppings,
chemicals from industrial chimneys, etc., can
damage the vehicle's finish if they remain
on painted surfaces. Wash the vehicle as
soon as possible. If necessary, use
non-abrasive cleaners that are marked safe
for painted surfaces to remove foreign
matter.
Occasional hand waxing or mild polishing
should be done to remove residue from the
paint finish. See your dealer for approved
cleaning products.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
386 Vehicle Care
.Promptly rinse the bed surface following
a chemical spill to avoid permanent
damage.
.Use a dry rag to remove oil.
Cleaning Exterior Lamps/Lenses,
Emblems, Decals and Stripes
Use only lukewarm or cold water, a soft
cloth, and a car washing soap to clean
exterior lamps, lenses, emblems, decals and
stripes. Follow instructions under "Washing
the Vehicle" previously in this section.
Lamp covers are made of plastic, and some
have a UV protective coating. Do not clean
or wipe them while they are dry.
Do not use any of the following on lamp
covers:
.Abrasive or caustic agents.
.Washer fluids and other cleaning agents
in higher concentrations than suggested
by the manufacturer.
.Solvents, alcohols, fuels, or other harsh
cleaners.
.Ice scrapers or other hard items.
.Aftermarket appearance caps or covers
while the lamps are illuminated, due to
excessive heat generated.
Caution
Failure to clean lamps properly can cause
damage to the lamp cover that would
not be covered by the vehicle warranty.
Caution
Using wax on low gloss black finish
stripes can increase the gloss level and
create a non-uniform finish. Clean low
gloss stripes with soap and water only.
Air Intakes
Clear debris from the air intakes, between
the hood and windshield, when washing the
vehicle.
Shutter System
The vehicle may have a shutter system
designed to help improve fuel economy.
Keep the shutter system clear of debris,
snow and ice. If the check engine light is
activated, please check to see if the shutter
system is clear of debris, snow or ice.
Windshield and Wiper Blades
Clean the outside of the windshield with
glass cleaner.
Clean rubber blades using a lint-free cloth or
paper towel soaked with windshield washer
fluid or a mild detergent. Wash the
windshield thoroughly when cleaning the
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
388 Vehicle Care
Inspect power steering for proper
attachment, connections, binding, cracks,
chafing, etc.
Visually check constant velocity joint boots
and axle seals for leaks.
2500/3500 Series vehicles, at least every
engine oil change lubricate the upper and
lower control arm ball joints.
2500/3500 Series vehicles equipped with
steering linkage, at least every engine oil
change lubricate the tie rod ball joints, idler
arm pivot shaft bearings, idler arm socket,
and pitman arm socket.
Caution
Lubrication of applicable suspension
points should not be done unless the
temperature is−12 °C (10 °F) or higher,
or damage could result.
Body Component Lubrication
Lubricate all key lock cylinders, hood hinges,
liftgate hinges, and the steel fuel door hinge
unless the components are plastic. Applying
silicone grease on weatherstrips with a clean
cloth will make them last longer, seal better,
and not stick or squeak.
Underbody Maintenance
At least twice a year, spring and fall, use
plain water to flush any corrosive materials
from the underbody. Take care to
thoroughly clean any areas where mud and
other debris can collect. If equipped with
power assist steps, extend them and then
use a high pressure wash to clean all joints
and gaps.
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 axles and should be replaced.
Sheet Metal Damage
If the vehicle is damaged and requires sheet
metal repair or replacement, make sure the
body repair shop applies anti-corrosion
material to parts repaired or replaced to
restore corrosion protection.
Original manufacturer replacement parts will
provide the corrosion protection while
maintaining the vehicle warranty.
Finish Damage
Quickly repair minor chips and scratches
with touch-up materials available from your
dealer to avoid corrosion. Larger areas of
finish damage can be corrected in your
dealer's body and paint shop.
Chemical Paint Spotting
Airborne pollutants can fall upon and attack
painted vehicle surfaces causing blotchy,
ring-shaped discolorations, and small,
irregular dark spots etched into the paint
surface. Refer to “Finish Care”previously in
this section.
Interior Care
To prevent dirt particle abrasions, regularly
clean the vehicle's interior. Before using
cleaners, read and follow all safety
instructions on the label. While cleaning the
interior, open the doors and windows to get
proper ventilation. Newspapers or dark
garments can transfer color to the vehicle’s
interior.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Vehicle Care 389
Caution
Immediately remove cleaners, hand
lotions, sunscreen, and insect repellent
from all interior surfaces or permanent
damage may result.
Caution
Use cleaners specifically designed for the
surfaces being cleaned to prevent
permanent damage to the vehicle. Apply
all cleaners directly to a cleaning cloth.
Do not spray cleaners on any switches or
controls.
When using liquid soap cleaners, follow the
directions on the specific cleaner or soap
solution for dilution instructions.
Caution
To prevent damage:
.Never use a razor or any other sharp
object to remove soil from any interior
surface
.Never use a brush with stiff bristles.(Continued)
Caution (Continued)
.Never rub any surface aggressively or
with too much pressure.
.Do not get any exposed electrical
components wet.
.Do not use laundry detergents or
dishwashing soaps with degreasers. Do
not use solutions that contain strong
or caustic soap.
.Do not heavily saturate the upholstery
when cleaning.
.Do not use solvents or cleaners
containing solvents.
.Do not use disinfecting wipes that are
scented or contain bleach. Do not use
wipes or cleaners that show a color
transfer to the wipe or change the
appearance of the interior surface
when used.
.Do not use scented or gel-type hand
sanitizers. If hand sanitizer comes in
contact with interior surfaces of the
vehicle, blot immediately and clean
with a soft cloth dampened with a
mild soap and water solution.
Interior Glass
To clean, use a microfiber cloth fabric
dampened with water. Wipe droplets left
behind with a clean dry cloth. If necessary,
use a commercial glass cleaner after
cleaning with plain water.
Caution
To prevent scratching, never use abrasive
cleaners on automotive glass. Abrasive
cleaners or aggressive cleaning may
damage the rear window defogger.
Cleaning the windshield with water during
the first three to six months of ownership
will reduce tendency to fog.
Speaker Covers
Vacuum around a speaker cover gently, so
that the speaker will not be damaged. Clean
spots with water and mild soap.
Coated Moldings
Coated moldings should be cleaned.
.When lightly soiled, wipe with a sponge
or soft, lint-free cloth dampened with
water.
.When heavily soiled, use warm soapy
water.