2021 CHEVROLET SILVERADO 1500 headlamp

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
320 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 321
California Proposition 65 Warning . . . . . 321
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 321
Accessories and Modifications . . . . . . . . . 322
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 322
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Engine Compartment Overview . . . . . . . . 324
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Engine Oil Life System . . . . . . . . . . . . . . . . . 331
Automatic Transmission Fluid . . . . . . . . . . 332
Engine Air Filter Life System . . . . . . . . . . . 332
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 333
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 334
Engine Overheating . . . . . . . . . . . . . . . . . . . . 337
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . 339
Engine Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 339
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Brake Pad Life System . . . . . . . . . . . . . . . . . 341
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342
Battery - North America . . . . . . . . . . . . . . . 342 Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 345
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345
Starter Switch Check . . . . . . . . . . . . . . . . . . 346
Automatic Transmission Shift Lock
Control Function Check . . . . . . . . . . . . . . 346
Ignition Transmission Lock Check . . . . . . 346
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
Wiper Blade Replacement . . . . . . . . . . . . . 347
Glass Replacement . . . . . . . . . . . . . . . . . . . . 347
Windshield Replacement . . . . . . . . . . . . . . 347
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . 348
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 349
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 349
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 349
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps . . . . . 349
Taillamps, Turn Signal, Stoplamps, and Back-Up Lamps . . . . . . . . . . . . . . . . . . . . . . 350
Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp . . . . . . . . . . . . 352
License Plate Lamp . . . . . . . . . . . . . . . . . . . . 352
Electrical System
Electrical System Overload . . . . . . . . . . . . . 352
Fuses and Circuit Breakers . . . . . . . . . . . . . 353
Engine Compartment Fuse Block . . . . . . . 353
Instrument Panel Fuse Block (Left) . . . . . 357
Instrument Panel Fuse Block (Right) . . . 358
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 361
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . 362
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 362
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 364
Tire Terminology and Definitions . . . . . . 365
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Tire Pressure Monitor System . . . . . . . . . 368
Tire Pressure Monitor Operation . . . . . . 369
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 374
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 374
When It Is Time for New Tires . . . . . . . . 375
Buying New Tires . . . . . . . . . . . . . . . . . . . . . 376
Different Size Tires and Wheels . . . . . . . . 377
Uniform Tire Quality Grading . . . . . . . . . . 377
Wheel Alignment and Tire Balance . . . . 379
Wheel Replacement . . . . . . . . . . . . . . . . . . . 379
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 380
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . . 381
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . . 391

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
Vehicle Care 349
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.
Bulb Replacement
For the proper type of replacement bulbs,
or any bulb changing procedure not listed in
this section, contact your dealer.
Caution
Do not replace incandescent bulbs with
aftermarket LED replacement bulbs. This
can cause damage to the vehicle electrical
system.
Halogen Bulbs
{Warning
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the
bulb. You or others could be injured. Be
sure to read and follow the instructions
on the bulb package.
LED Lighting
This vehicle has several LED lamps. For
replacement of any LED lighting assembly,
contact your dealer.
Headlamps, Front Turn Signal,
Sidemarker, and Parking Lamps
Base Level Headlamp Assembly
1. Sidemarker lamp
2. Low-Beam Headlamp
3. High-Beam Headlamp
4. Turn Signal/Park Lamps

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
350 Vehicle Care
Midlevel Headlamp Assembly
1. Turn Signal Lamps
Headlamp Replacement
Base Level1. Open the hood.
2. Remove the headlamp bulb cover.
3. Turn the bulb socket counterclockwise to remove it from the headlamp assembly.
4. Unplug the electrical connector from the bulb by releasing the clip on the
connector.
5. Replace the bulb and reverse Steps 1–4 to reinstall. Midlevel and Uplevel
See your dealer for headlamp replacement.
Uplevel
See your dealer for turn signal replacement.
Turn Signal Lamp Replacement
1. Open the hood.
2. Turn the bulb socket counterclockwise to
remove it from the headlamp assembly
and pull it straight out.
3. Remove the bulb by pulling it straight out of the bulb socket.
4. Replace the bulb and reverse Steps 1–3 to reinstall.
Taillamps, Turn Signal, Stoplamps,
and Back-Up Lamps
Base Level Taillamp Assembly
1. Stoplamp/Taillamp/Turn Signal Lamp
2. Back-Up Lamp
3. Side Marker Lamp

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
Vehicle Care 353
Choose some feature of the vehicle that is
not needed to use and replace it as soon as
possible.
Headlamp Wiring
An electrical overload may cause the lamps
to go on and off, or in some cases to
remain off. Have the headlamp wiring
checked right away if the lamps go on and
off or remain off.
Windshield Wipers
If the wiper motor overheats due to heavy
snow or ice, the windshield wipers will stop
until the motor cools and will then restart.
Although the circuit is protected from
electrical overload, overload due to heavy
snow or ice may cause wiper linkage
damage. Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an electrical
problem and not snow or ice, be sure to get
it fixed.
Fuses and Circuit Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit breakers.
This greatly reduces the chance of damage
caused by electrical problems.
{Danger
Fuses and circuit breakers are marked
with their ampere rating. Do not exceed
the specified amperage rating when
replacing fuses and circuit breakers. Use
of an oversized fuse or circuit breaker can
result in a vehicle fire. You and others
could be seriously injured or killed.
{Warning
Installation or use of fuses that do not
meet GM’s original fuse specifications is
dangerous. The fuses could fail, and result(Continued)
Warning (Continued)
in a fire. You or others could be injured
or killed, and the vehicle could be
damaged.
See Accessories and Modifications 0322 and
General Information 0321.
To check a fuse, look at the silver-colored
band inside the fuse. If the band is broken
or melted, replace the fuse. Be sure to
replace a bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can be
temporarily borrowed from another fuse
location, if a fuse goes out. Replace the fuse
as soon as possible.
Engine Compartment Fuse Block
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
The engine compartment fuse block is in the
engine compartment, on the passenger side
of the vehicle.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
354 Vehicle Care
Lift the cover to access the fuse block.
Caution
Spilling liquid on any electrical
component on the vehicle may damage
it. Always keep the covers on any
electrical component.
A fuse puller is available in the left
instrument panel end cap.
The vehicle may not be equipped with all of
the fuses, relays, and features shown.
Fuses Usage
1 High-beam left
2 High-beam right Fuses
Usage
3 Headlamp left
4 Headlamp right

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
356 Vehicle Care
FusesUsage
65 Auxiliary underhood electrical center
66 Cooling fan motor left 67 Active fuel management 2
68 –
69 Starter Pinion (LD) / Starter Motor (HD Gas)
71 Cooling fan
72 Cooling fan right/Lower
73 Trailer stop/turn lamp left
74 Trailer Interface Module 1
75 DEFC
76 Electric RNG BDS
78 Engine control module
79 Auxiliary battery
80 Cabin cooling pump 81 Trailer stop/turn lamp right Fuses
Usage
82 Trailer Interface Module 2
83 FTZM
84 Trailer brake 85 ENG
86 Engine control module 87 Injector B even
88 O2 B sensor
89 O2 A sensor
90 Injector A odd 91 Engine control module throttle control
92 Cool fan clutch/ Aeroshutter Relays
Usage
5 Headlamp
18 DC/AC inverter
23 Rear window defogger
35 Parking lamp
36 Run/Crank
43 –
59 A/C clutch
64 Starter Motor (LD & HD DSL)
70 Starter Pinion (LD) / Starter Motor (HD Gas)
77 Powertrain

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
Vehicle Care 379
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider an
alignment check if there is unusual tire wear
or the vehicle is significantly pulling to one
side or the other. Some slight pull to the
left or right, depending on the crown of the
road and/or other road surface variations
such as troughs or ruts, is normal. If the
vehicle is vibrating when driving on a
smooth road, the tires and wheels may
need to be rebalanced. See your dealer for
proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked,
or badly rusted or corroded. If wheel nuts
keep coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If the
wheel leaks air, replace it. Some aluminum
wheels can be repaired. See your dealer if
any of these conditions exist.Your dealer will know the kind of wheel that
is needed.
Each new wheel should have the same
load-carrying capacity, diameter, width,
offset, and be mounted the same way as
the one it replaces.
Replace wheels, wheel bolts, wheel nuts,
or Tire Pressure Monitor System (TPMS)
sensors with new GM original equipment
parts.
{Warning
Using the wrong replacement wheels,
wheel bolts, or wheel nuts can be
dangerous. It could affect the braking and
handling of the vehicle. Tires can lose air,
and cause loss of control, causing a crash.
Always use the correct wheel, wheel
bolts, and wheel nuts for replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake cooling,
speedometer or odometer calibration,
headlamp aim, bumper height, vehicle
ground clearance, and tire or tire chain
clearance to the body and chassis.
Used Replacement Wheels
{Warning
Replacing a wheel with a used one is
dangerous. How it has been used or how
far it has been driven may be unknown.
It could fail suddenly and cause a crash.
When replacing wheels, use a new GM
original equipment wheel.
Tire Chains
{Warning
If the vehicle has 275/50R22, 275/60R20,
LT265/60R20, LT265/70R17, or LT275/65R18
size tires, do not use tire chains. There is
not enough clearance. Tire chains used on
a vehicle without the proper amount of
clearance can cause damage to the
brakes, suspension, or other vehicle parts.
The area damaged by the tire chains
could cause loss of control and a crash.
Use another type of traction device only
if its manufacturer recommends it for the
vehicle's tire size combination and road
conditions. Follow that manufacturer's
(Continued)

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-14632303) - 2021 - CRC - 11/9/20
416 Service and Maintenance
.Trained dealer technicians have the
diagnostic equipment to test the battery
and ensure that the connections and
cables are corrosion-free.
Belts
.Belts may need replacing if they squeak
or show signs of cracking or splitting.
.Trained dealer technicians have access to
tools and equipment to inspect the belts
and recommend adjustment or
replacement when necessary.
Brakes
Brakes stop the vehicle and are crucial to
safe driving.
.Signs of brake wear may include chirping,
grinding, or squealing noises, or difficulty
stopping.
.Trained dealer technicians have access to
tools and equipment to inspect the brakes
and recommend quality parts engineered
for the vehicle.
Fluids
Proper fluid levels and approved fluids
protect the vehicle’s systems and
components. See Recommended Fluids and
Lubricants 0418 for GM approved fluids.
.Engine oil and windshield washer fluid
levels should be checked at every fuel fill.
.Instrument cluster lights may come on to
indicate that fluids may be low and need
to be filled.
Hoses
Hoses transport fluids and should be
regularly inspected to ensure that there are
no cracks or leaks. With a multi-point
inspection, your dealer can inspect the hoses
and advise if replacement is needed.
Lamps
Properly working headlamps, taillamps, and
brake lamps are important to see and be
seen on the road.
.Signs that the headlamps need attention
include dimming, failure to light, cracking,
or damage. The brake lamps need to be
checked periodically to ensure that they
light when braking.
.With a multi-point inspection, your dealer
can check the lamps and note any
concerns.
Shocks and Struts
Shocks and struts help aid in control for a
smoother ride.
.Signs of wear may include steering wheel
vibration, bounce/sway while braking,
longer stopping distance, or uneven
tire wear.
.As part of the multi-point inspection,
trained dealer technicians can visually
inspect the shocks and struts for signs of
leaking, blown seals, or damage, and can
advise when service is needed.
Tires
Tires need to be properly inflated, rotated,
and balanced. Maintaining the tires can save
money and fuel, and can reduce the risk of
tire failure.
.Signs that the tires need to be replaced
include three or more visible treadwear
indicators; cord or fabric showing through
the rubber; cracks or cuts in the tread or
sidewall; or a bulge or split in the tire.
.Trained dealer technicians can inspect and
recommend the right tires. Your dealer
can also provide tire/wheel balancing
services to ensure smooth vehicle
operation at all speeds. Your dealer sells
and services name brand tires.