2021 CHEVROLET COLORADO tires

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Instruments and Controls 9
Malfunction Indicator Lamp
(Check Engine Light)
This light is part of the vehicle’s emission
control on-board diagnostic system. If this
light is on while the engine is running, a
malfunction has been detected and the
vehicle may require service. The light should
come on to show that it is working when
the ignition is on with the engine not
running. See“Ignition Positions” in the
owner’s manual.
This light may also come on when the
system has detected a problem with the
Diesel Exhaust Fluid (DEF) management
system. See Diesel Exhaust Fluid 022.
Malfunctions are often indicated by the
system before any problem is noticeable.
Being aware of the light and seeking service
promptly when it comes on may prevent
damage.
Caution
If the vehicle is driven continually with
this light on, the emission control system
may not work as well, the fuel economy
may be lower, and the vehicle may not
run smoothly. This could lead to costly
repairs that might not be covered by the
vehicle warranty.
Caution
Modifications to the engine, transmission,
exhaust, intake, or fuel system, or the
use of replacement tires that do not
meet the original tire specifications, can
cause this light to come on. This could
lead to costly repairs not covered by the
vehicle warranty. This could also affect
the vehicle’s ability to pass an Emissions
Inspection/Maintenance test. See
Accessories and Modifications 052.
When the light is on, a malfunction has
been detected. Diagnosis and service may be
required.
Poor fuel quality can cause inefficient engine
operation and poor driveability, which may
go away once the engine is warmed up. If this occurs, change the fuel brand. It may
require at least one full tank of the proper
fuel to turn the light off. See
Fuel for Diesel
Engines 025.
If the light remains on, see your dealer.
Emissions Inspection and Maintenance
Programs
If the vehicle requires an Emissions
Inspection/Maintenance test, the test
equipment will likely connect to the
vehicle's Data Link Connector (DLC).
The DLC is under the instrument panel to
the left of the steering wheel. Connecting
devices that are not used to perform an
Emissions Inspection/Maintenance test or to
service the vehicle may affect vehicle
operation. See “Add-On Electrical Equipment”
in the owner’s manual. See your dealer if
assistance is needed.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Driving and Operating 37
See“Trailer Towing” in the owner’s manual
for kingpin weight and trailer tongue weight
information.
Weight of the Trailer Tongue
The tongue weight load (1) of any trailer is
very important because it is also part of the
vehicle weight. The Gross Vehicle
Weight (GVW) includes the curb weight of
the vehicle, any cargo carried in it, and the
people who will be riding in the vehicle as
well as trailer tongue weight. Vehicle
options, equipment, passengers, and cargo
in the vehicle reduce the amount of tongue
weight the vehicle can carry, which will also
reduce the trailer weight the vehicle
can tow.
The trailer tongue weight (1) should be
10-15% of the total loaded trailer (2). For
Vans: The trailer tongue weight (1) can use a
weight carrying hitch for up to 181 kg
(400 lb). Greater than 181 kg (400 lb), a
weight distribution hitch is required with a
maximum of 454 kg (1,000 lb)
Do not exceed the maximum allowable
tongue weight for the vehicle. Choose the
shortest hitch extension that will position
the hitch ball closest to the vehicle. This will
help reduce the effect of trailer tongue
weight on the rear axle.
Trailer rating may be limited by the vehicle's
ability to carry tongue weight. Tongue or
kingpin weight cannot cause the vehicle to
exceed the GVWR (Gross Vehicle Weight
Rating) or the RGAWR (Rear Gross Axle
Weight Rating). See “Total Weight on the
Vehicle's Tires” in the owner’s manual.
After loading the trailer, weigh the trailer
and then the tongue, separately, to see if
the weights are proper. If they are not,
adjustments might be made by moving
some items around in the trailer.
If a cargo carrier is used in the trailer hitch
receiver, choose a carrier that positions the
load as close to the vehicle as possible.
Make sure the total weight, including the carrier, is no more than half of the
maximum allowable tongue weight for the
vehicle or 227 kg (500 lb), whichever is less.
Conversions and Add-Ons
Power Take-Off (PTO)
If equipped, the Power Take-Off (PTO) is a
GM Upfitter integrated system that is used
to create an auxiliary power source for
running add-on equipment, such as salt
spreaders, snow plows, winches, and lift
buckets. The PTO system controls engine
speed to values higher than normal base
idle, PTO load relay engagement, and
remote starting and shutdown of the
engine.
When installing PTO aftermarket equipment,
the PTO wiring and operation
recommendations provided by the service
manual and GM Upfitter documentation
must be strictly followed.
Refer to the bulletins in the GM Upfitter
Integration website www.gmupfitter.com for
the Power Take-Off (PTO) operating
description and application guide.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
72 Service and Maintenance
Service and Maintenance
General Information
General Information . . . . . . . . . . . . . . . . . . . . 72
Maintenance Schedule
Maintenance Schedule . . . . . . . . . . . . . . . . . . 73
Maintenance Schedule . . . . . . . . . . . . . . . . . . 77
Recommended Fluids, Lubricants, and
Parts
Recommended Fluids and Lubricants . . . 78
Maintenance Replacement Parts . . . . . . . . 79
Maintenance Records
Maintenance Records . . . . . . . . . . . . . . . . . . . 80
General Information
This maintenance section applies to vehicles
with a diesel engine. For gasoline engine
vehicles, see the maintenance schedule
section in the owner’s manual.
Your vehicle is an important investment.
This section describes the required
maintenance for the vehicle. Follow this
schedule to help protect against major repair
expenses resulting from neglect or
inadequate maintenance. It may also help to
maintain the value of the vehicle if it is
sold. It is the responsibility of the owner to
have all required maintenance performed.
Your dealer has trained technicians who can
perform required maintenance using genuine
replacement parts. They have up-to-date
tools and equipment for fast and accurate
diagnostics. Many dealers have extended
evening and Saturday hours, courtesy
transportation, and online scheduling to
assist with service needs.Your dealer recognizes the importance of
providing competitively priced maintenance
and repair services. With trained technicians,
your dealer is the place for routine
maintenance such as oil changes and tire
rotations and additional maintenance items
like tires, brakes, batteries, and wiper blades.
Caution
Damage caused by improper maintenance
can lead to costly repairs and may not be
covered by the vehicle warranty.
Maintenance intervals, checks,
inspections, recommended fluids, and
lubricants are important to keep the
vehicle in good working condition.
Do not have chemical flushes that are not
approved by GM performed on the
vehicle. The use of flushes, solvents,
cleaners, or lubricants that are not
approved by GM could damage the
vehicle, requiring expensive repairs that
are not covered by the vehicle warranty.