
Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Instruments and Controls 3
Instruments and Controls
Warning Lights, Gauges, and Indicators
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . 4
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Engine Oil Pressure Gauge . . . . . . . . . . . . . . . 8
Malfunction Indicator Lamp (Check EngineLight) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Wait-to-Start Light . . . . . . . . . . . . . . . . . . . . . . 10
Diesel Exhaust Fluid (DEF) Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Power Take-Off Light (Chassis Cab Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Information Displays
Driver Information Center (DIC) . . . . . . . . . 10
Vehicle Personalization
Vehicle Personalization (Van Models) . . . . 11
Vehicle Personalization (PickupModels) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
4 Instruments and Controls
Warning Lights, Gauges, and Indicators
Instrument Cluster
English Base Level 4-Cylinder Pickup Shown, Metric Similar

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
10 Instruments and Controls
The vehicle may not pass inspection if:
.The light is on when the engine is
running.
.The light does not come on when the
ignition is on with the engine not
running.
.Critical emission control systems have not
been completely diagnosed. If this
happens, the vehicle would not be ready
for inspection and might require
several days of routine driving before the
system is ready for inspection. This can
happen if the 12-volt battery has recently
been replaced or run down, or if the
vehicle has recently been serviced.
See your dealer if the vehicle will not pass
or cannot be made ready for the test.
Wait-to-Start Light
This light comes on briefly while starting
the engine, as a check to show the light is
working. If the wait-to-start light comes on, the glow
plug system is required and operating. Wait
until the light turns off before starting the
engine. This light may not come on in warm
temperatures.
The fast warm-up glow plug system makes
the wait-to-start light stay on for a shorter
amount of time than most diesel engines.
See
Starting the Diesel Engine 013.
Diesel Exhaust Fluid (DEF)
Warning Light
This light, a Driver Information Center (DIC)
message, and a chime come on when there
is an issue with the Diesel Exhaust Fluid.
If the DEF level has not been corrected, the
light will continue to flash when the vehicle
is started. The vehicle's speed may also be
limited.
Also see Diesel Exhaust Fluid 022.
Power Take-Off Light (Chassis
Cab Only)
Chassis Cab
The vehicle may have a Power Take-Off
(PTO) light. Under normal operating
conditions, the PTO light will remain on
throughout the PTO operating cycle. If all
conditions required to engage PTO have not
been met when enabling PTO, the PTO light
will turn on, then turn off after one second.
See Power Take-Off (PTO) 037.
Information Displays
Driver Information Center (DIC)
The DIC is in the instrument cluster. The DIC
comes on when the ignition is on.
A Duramax diesel vehicle may have the
following additional DIC menu items:

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
20 Driving and Operating
Caution (Continued)
Recommended Fluids and Lubricants
section of this manual are not used. This
damage would not be covered by the
vehicle warranty.
Under certain driving conditions, such as
stop-and-go traffic, the filter cannot clean
itself. A message comes on when the DPF is
dirty and needs to perform a self cleaning.
For the filter to clean itself, the vehicle must
be driven above 50 km/h (30 mph) until the
message goes off. This will take about
30 minutes.
{Warning
During DPF self-cleaning or during
extended idling in P (Park), the exhaust
system and exhaust gases are very hot.
Things that burn could touch hot exhaust
parts under the vehicle and ignite. You or
others could be burned. Do not park,
or idle for an extended period of time,
near or over papers, leaves, dry grass,
or other things that can burn. Keep the (Continued)
Warning (Continued)
exhaust area clear of material that could
ignite or burn. SeeParking over Things
That Burn 019.
Caution
Extended idle should be avoided because
the DPF system is not capable of self
cleaning at idle. During extended idle
operation, monitor the instrument cluster
telltale lights and Driver Information
Center for messages and take appropriate
indicated action. Continued idling with
the warning light/message on could
cause irreversible damage to the DPF
requiring repair and possible replacement
that might not be covered by the vehicle
warranty.
You will also notice a change in the exhaust
sound and engine idle speed. Along with
this, a burning smell and reduction in fuel
economy may be noticed. This is normal.
If you continue to drive with the DPF
warning message on and the exhaust filter
is not cleaned as required, the malfunction
indicator lamp and the ENGINE POWER IS REDUCED message will come on and dealer
service is necessary. See
Malfunction
Indicator Lamp (Check Engine Light) 09.
Vehicles with the DPF have specific fuel and
engine oil requirements. See Fuel for Diesel
Engines 025 and
Engine Oil 055.
Extended idling in P (Park) can cause exhaust
parts and gases to become very hot. Keep
the exhaust area clear of material that could
ignite or burn. See Parking over Things That
Burn 019.
If equipped with Power Take-Off (PTO),
monitor the instrument cluster for lights
related to the DPF.
See Accessories and Modifications 052 for
important information if you are considering
adding accessories or modifying the vehicle.
Manual Regeneration of Diesel
Particulate Filter
This feature is only available on Fleet and
Commercial vehicles.
To verify that the vehicle has this feature,
refer to the Vehicle Service Parts
Identification label (SPID) for RPO code FPF

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Driving and Operating 25
Pickups
Vans
The exhaust brake is activated when Tow/
Haul Mode is activated. See “Tow/Haul
Mode” in the owner’s manual. A light comes on in the instrument cluster
when the exhaust brake and Tow/Haul are
activated. The switch must be pressed at
each vehicle start for the system to be
active.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER Diesel
Fuel to keep the engine clean, reduce engine
deposits, and maintain optimal vehicle
performance. Look for the TOP TIER Logo or
see www.toptiergas.com for a list of TOP
TIER Diesel Fuel marketers and applicable
countries.
Fuel Additives
TOP TIER Detergent Diesel is highly
recommended for use with your vehicle.
If your area does not have TOP TIER
Detergent Diesel, GM recommends the use
of ACDelco Diesel Fuel Conditioner. This will
help maintain optimal engine performance.
GM does not recommend other aftermarket
diesel additives.
If low-quality diesel is used for refueling,
GM recommends adding ACDelco Fuel
System Treatment Plus-Diesel to help clean
engine deposits. This is available at your GM
dealer.
Fuel for Diesel Engines
The selection of a high-quality fuel is
important for maintaining optimum vehicle
performance. Diesel fuel should meet or
exceed the minimum requirements in the
most current versions of the local fuel
standards.
Do not use fuel with more than 15 ppm
sulfur, commonly referred to as Ultra Low
Sulfur Fuel.
Do not use a diesel blend containing more
than 20% biodiesel by volume.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
62 Vehicle Care
Warning (Continued)
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If no coolant is visible in the surge tank, add
coolant as follows:
2.8L 4-Cylinder Van Pressure Cap
1. Remove the coolant surge tank pressure cap when the cooling system, including
the coolant surge tank pressure cap and
upper radiator hose, is no longer hot.
Turn the pressure cap slowly
counterclockwise about one full turn. If a
hiss is heard, wait for that to stop.
A hiss means there is still some
pressure left.
2. Keep turning the pressure cap slowly, and remove it. 3. Slowly fill the coolant surge tank. Do not
let the coolant level go above the
indicated mark in the tank until after the
engine comes to operating temperature
in Step 4.
4. With the coolant surge tank pressure cap off, start the engine and let it run until
the engine coolant temperature gauge
indicates approximately 90 °C (195 °F).
By this time, the coolant level inside the
coolant surge tank may be lower. If the
level is lower, slowly add more of the
proper mixture to the coolant surge tank
until it reaches the indicated mark.
5. Re-install the pressure cap. Be sure the pressure cap is hand-tight
and fully seated.
6. Verify coolant level after the engine is shut off and the coolant is cold.
If necessary, repeat Steps 1–6.
If the coolant level is still low after having
followed these steps twice, have the coolant
system checked by a certified technician at
the dealer for a possible leak.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.
Engine Overheating
There is an engine coolant temperature
gauge on the instrument cluster. See the
owner’s manual.
If Steam Is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Vehicle Care 69
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Fuses Usage
1 Antilock brake system motor
2 Antilock brake system module
3 Right trailer stoplamp/ Turnlamp
4 –
5 –
6 Fuel system control module/Ignition
7 Body control module 5
8 Body control module 7
9 Body control module 4
10 Instrument cluster 11 Trailer wiring
12 –
13 Display/Mirrors/Rear vision camera
14 Washer
16 Horn Fuses Usage
17 Transmission
18 Air conditioning
19 Engine control module battery
20 Left stop/turn cutaway lamp
21 Left stop/turn trailer lamp
22 Right stop/turn cutaway lamp
23 NOx sensors
24 Diesel fuel pump 25 Auxiliary power outlet
26 Body control module 3 27 Special equipment option
28 Airbag
29 Steering wheel sensor
30 Engine control module/ Glow plug module/
Ignition Fuses Usage
31 Transmission control module/Ignition
32 Transmission control module battery
33 Obstacle detection
34 NOx sensors 35 Fuel operated heater module
36 Fuel system control module battery
41 Transmission control module 2, battery
signal
42 Trailer wiring
43 EV fan clutch
44 Starter solenoid 45 Engine control module, powertrain signal 1
46 DC-AC inverter 47 Cooling fan –low
51 Left high-beam headlamp

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Index 85
IndexA
Accessories and Modifications . . . . . . . . . . . . .52
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . . 58
Appearance CareExterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 58
B
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Biodiesel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
BrakeExhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
C
Canadian Vehicle Owners . . . . . . . . . . . . . . . . . . . 1
Capacities and Specifications . . . . . . . . . . . . . . 82
CheckEngine Light (Malfunction Indicator) . . . . . 9
Cleaning Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Cluster, Instrument . . . . . . . . . . . . . . . . . . . . . . . . 4
Cold Weather Operation . . . . . . . . . . . . . . . . . . .27
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Covers Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
D
DieselStarting Your Engine . . . . . . . . . . . . . . . . . . . . . 13
Diesel Exhaust Fluid . . . . . . . . . . . . . . . . . . . . . . .22
Diesel Exhaust Fluid (DEF) Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Diesel Particulate Filter . . . . . . . . . . . . . . . . . . . .19
Drive Belt Routing, Engine . . . . . . . . . . . . . . . . 84
Driver Information Center (DIC) . . . . . . . . . . . 10
E
Electrical System Engine Compartment Fuse Block . . . . . . . . 64
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . 58
Check Light (Malfunction Indicator) . . . . . . 9
Compartment Overview . . . . . . . . . . . . . . . . . 53
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . 60
Drive Belt Routing . . . . . . . . . . . . . . . . . . . . . . 84
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . . 58
Oil Pressure Gauge . . . . . . . . . . . . . . . . . . . . . . 8
Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Starting Your Diesel . . . . . . . . . . . . . . . . . . . . . 13
Engines Diesel Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Exhaust Brake . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24