the vanes by a linkage rod. The vanes are used to vary
the amount of boost pressure and can control the boost
pressure independent of engine speed. The vanes
mount to a unison ring which is rotated to change the
vane angle. The ECM will vary the vane angle which
adjusts the boost dependent upon the load
requirements of the engine.
When the actuator arm is in the vertical top rest position
the turbocharger vanes are fully open. When the
actuator arm is in the horizontal bottom of travel
position the turbocharger vanes are fully closed.
The turbocharger vanes are normally open when the
engine is not under load. However, the ECM will often
close the turbocharger vanes to create back pressure
to drive exhaust gas through the Exhaust Gas

Page 28

November, 2019

Recirculation (EGR) valve as required. At extreme cold
temperatures, the ECM may close the vanes at low
load conditions in order to accelerate engine coolant
heating.
The turbocharger is also utilized as a component of the
exhaust brake system. Under certain conditions, the
ECM will automatically close the turbocharger vanes to
build back pressure in the exhaust, which reduces
engine speed and slows the vehicle without applying
the brakes.
During regeneration, the ECM will vary the
turbocharger vanes to assist with the exhaust system
warm-up, and to maintain proper engine exhaust
temperatures needed to properly regenerate the Diesel
Exhaust Particulate Filter (DPF).
Each time the ignition is turned OFF, the turbocharger
vane position actuator performs a learn procedure. The
actuator arm sweeps the turbocharger vanes from fully
open to fully closed to obtain a count value. This value
is compared to the previous value to ensure proper
vane position. Following the learn sweep the actuator
sweeps the vanes two more times to clean off
combustion soot.

Bulletin No.: 18-NA-366

3. Select the desired feature and setting. Settings are
saved automatically.
4. . Select BACK to exit each menu.
Bluetooth®
The Bluetooth® system allows users with a Bluetooth®
enabled cell phone to make and receive hands-free
calls using the vehicle audio system and controls.
Before using a Bluetooth® enabled device in the
vehicle, it must be paired with the in-vehicle Bluetooth®
system. The pairing process is disabled when the
vehicle is moving. When using the Bluetooth system,
sound comes through the vehicle's front audio system
speakers and overrides the audio system. Use the
volume control knob during a call to change the volume
level. The system maintains a minimum volume level.
Not all devices will support all functions.
Accessory Power Outlets — 110 Volt Power Outlet
— USB Ports
Depending on the type of seat

Vehicle Hoisting/Lifting
The Service Department will need a 25,000 pound
Hoist/Lift to raise the vehicle. For safety reasons, DO
NOT use jackstands or floor jacks.

Vehicle Personalization

5186598

•

5186413

Some vehicle features can be customized using the
Settings menus on the infotainment system. The
Settings menus may include Time and Date, Language,
Radio, Vehicle, Bluetooth, Apple CarPlay, Android
Auto, Voice, Display, Return to Factory Settings,
Software Information, Wi-Fi, and more.
1. Select Settings on the Home page.
2. Select the desired menu item.

Vehicles with bench seats have an accessory
power outlet and 110 volt power outlet that are
located on the lower-center of the instrument
panel. USB ports and an accessory power outlet
are located in the center seat storage
compartment.

Bulletin No.: 18-NA-366

November, 2019

Page 29

Gross Combined Weight Rating
Note: It is important to remember that the GCWR is
not an actual measurement of the weight of a tow
vehicle and a trailer, but rather the combined
maximum weight limit that the manufacturer has set
for the two vehicles once attached.

5186733

•

Vehicles with bucket seats have USB ports,
accessory power outlets and a 110 volt power
outlet that are located on the center console. USB
ports and an accessory power outlet also are
located in the center console storage
compartment.

Vehicle Label — Incomplete
A vehicle-specific Incomplete Vehicle Label is attached
to the driver-side door frame. The upfitter will add an
additional Label upon completion of the work to the
vehicle, directly above the Incomplete Vehicle Label.
Curb Weight
Curb Weight is the weight of a vehicle without the
driver, passengers or cargo but including the maximum
capacity of fuel, oil, coolant and other items of standard
equipment.
Gross Axle Weight Rating
Note: It is important to remember that a vehicle's
GAWR is not a measurement of how much weight
each axle is actually carrying at any given time. The
actual amount of weight each axle is carrying is the
gross axle weight or GAW.
A vehicle's GAWR is the specific weight determined by
the manufacturer to be the maximum allowable weight
that can be placed on an individual axle. Front and rear
axles have individual gross axle weight ratings. The
GAWR is a weight limit for each of the vehicle's axles
which is determined by the manufacturer. A vehicle's
axles should never be loaded beyond the
manufacturer's listed GAWR. The GAWR includes the
weight of the vehicle, passengers, cargo and trailer
tongue weight (if equipped). Of course, all of this weight
is distributed between two axles.

A specific vehicle’s GCWR is based on parameters
established by chassis manufacturers. The
manufacturer makes an assessment in accordance
with SAE International test protocols, determining
maximum GCWR. Additionally, the OEM runs stringent
tests based on internal requirements which may include
testing total GCWR braking capability using only the
towing vehicle chassis braking system. GCWR is the
total weight of the truck pulling the trailer and the trailer
itself. The truck chassis dictates proper GCWR for safe
operation of the combination truck and trailer. GCWR is
the total allowable weight of the completely loaded
vehicle and trailer including fuel, passengers, cargo,
equipment, and accessories. Do not exceed the GCWR
for the vehicle.
• 4500HD Regular/Crew Cab: GCWR 26,000–
30,000 lbs.
• 5500HD Regular/Crew Cab: GCWR 26,000–
30,000 lbs.
• 6500HD Regular/Crew Cab: GCWR 26,000–
30,000 lbs.
Gross Combined Weight Rating — Calculating
To check that the weight of the vehicle and trailer are
within the GCWR for the vehicle, follow these steps:
• Start with the "curb weight" from the trailering
information label.
• Add the weight of the trailer loaded with cargo and
ready for the trip.
• Add the weight of all passengers.
• Add the weight of all cargo in the vehicle.
• Add the weight of hitch hardware such as a draw
bar, ball, load equalizer bars and sway bars.
• Add the weight of any accessories or aftermarket
equipment added to the vehicle.
The resulting weight cannot exceed the GCWR of the
vehicle.
The gross combined weight can also be confirmed by
weighing the truck and trailer on a public scale. The
truck and trailer should be loaded for the trip with
passengers and cargo.
Gross Vehicle Weight Rating
Note: It is important to remember that the GVWR is
not a measurement of how much a vehicle actually
weighs. A vehicle's actual weight is the gross
vehicle weight, or GVW.
A truck’s GVWR is the maximum weight rating
established by the chassis manufacturer. The OEM will
determine the GVWR based on test results and vehicle
dynamic performance to ensure a safe, reliable truck.
Safety standards that apply to braking, vehicle stability,
and chassis manufacturer internal standards for
durability, dynamic stability and handling can restrict
GVWR to less than the sum of the gross axle weight
ratings (GAWR) for that vehicle. The GVWR is

Page 30

November, 2019

Bulletin No.: 18-NA-366

calculated by adding the vehicle’s listed curb weight,
the weight of any optional accessories, cargo, the
trailer tongue weight (if equipped) and passengers.
• 4500HD Regular/Crew Cab: GVWR 15,000–
16,500 lbs.
• 5500HD Regular/Crew Cab: GVWR 17,500–
19,500 lbs.
• 6500HD Regular/Crew Cab: GVWR 21,000–
22,900 lbs.
Gross Vehicle Weight
Gross Vehicle Weight (GVW) is the total weight of the
truck and payload at a point in time and will vary. The
GVW includes the vehicle’s listed curb weight, cargo,
equipment, trailer tongue weight (if equipped) and
passengers. Vehicle options, passengers, cargo, and
equipment reduce the maximum allowable tongue
weight the vehicle can carry, which also reduces the
maximum allowable trailer weight.

Gross Combined Weight Rating Table
Use this table to determine the Gross Combined
Weight Rating (GCWR) based on the model and
equipment.

Transmission

Axle Ratio

Maximum Trailer
Weight (2)

GCWR*

4500/5500/
6500HD 2WD

Allison® 1700

4:10/4:30/4:56/4.88

(1)

26,000 lbs (11,818 kg)

4500/5500/
6500HD 2WD

Allison® 1750

4:10/4:30/4:56/4.88

(1)

30,000 lbs (16,636 kg)

6500HD 2WD

Allison® 2700

4:10/4:30/4:56/4.88

(1)

26,000 lbs (11,818 kg)

4500/5500/
6500HD 4WD

Allison® 1700

4:30

(1)

26,000 lbs (11,818 kg)

4500/5500/
6500HD 4WD

Allison® 1750

4:30

(1)

30,000 lbs (16,636 kg)

6500HD 4WD

Allison® 2700

4:30

(1)

26,000 lbs (11,818 kg)

Vehicle

*The GCWR is the total allowable weight of the completely loaded vehicle and trailer including passengers, cargo equipment and
conversions. The GCWR for the vehicle must not be exceeded.
(1) Maximum Trailer Weight cannot be provided because total vehicle weight is unknown.
(2) Choose an appropriate hitch and load the truck and trailer within the limits of GCWR, GVWR, and GAWR (of the Rear Axle).

Integrated Trailer Brake Control
The Integrated Trailer Brake Control (ITBC) system can
be used to adjust the amount of power output, or Trailer
Gain, available to the trailer brakes. The control panel
is located on the left side of the instrument panel. ITBC
information is displayed on the DIC.

Bulletin No.: 18-NA-366

November, 2019

Page 31

GM Upfitter Integration Group

Operation

Important: When adding non OE content to a
vehicle, contact the GM Upfitter Integration Group
for assistance if needed.
1. Click on: to visit the GM Upfitter Integration Group
Home Page. Scroll to the bottom of the page and
click on: Contact Us / Request Data
2. A request form will appear in a new window. To
request technical assistance from the GM Upfitter
Integration Group, complete and submit the form.

Warranty Coverage at a Glance
•
•
5182686

•

To operate the system:
• Squeeze the levers together on the control panel
(the left lever does not move) to manually apply
the trailer brakes.
• Adjust the Trailer Gain by pressing the +/–
adjustment buttons on the control panel.

Roadside Assistance
Overview
Owners of the new 2019 Chevrolet Silverado Chassis
Cab Medium Duty vehicles are automatically enrolled in
the Chevrolet Roadside Assistance program for up to
5 years/100,000 miles, whichever occurs first, at no
expense to you. Chevrolet’s Roadside Assistance
toll-free number is staffed by a team of trained advisors
who are available 24 hours a day, 365 days a year, to
contact a service provider for light services such as fuel
delivery, jump-starts, flat tire and lock-outs or to make
arrangements to have the vehicle towed to the nearest
Chevrolet Dealer for any repairs. Services are provided
for the duration of the vehicle’s powertrain warranty. For
U.S.-purchased vehicles, call 1-888-899-1327.
(Text Telephone (TTY): 1-888-889-2438).
OnStar® Roadside Assistance
If you have a current OnStar® Safety & Security plan,
push the blue OnStar® button or red Emergency button
to get the help you need. An OnStar® advisor will use
GPS technology to pinpoint the vehicle location and
contact the nearest service provider. To learn more
about OnStar® services, push the blue OnStar® button
or click on: or call 1-888-4-ONSTAR (1-888-466-7827).

•
•

Bumper-to-Bumper: (Includes Tires) Coverage
is for the first 3 years or 36,000 miles, whichever
comes first.
Powertrain: 6.6 Duramax® Turbo-Diesel Engine
coverage is provided for 5 years or 100,000 miles,
whichever comes first.
Powertrain: The General Motors Powertrain
warranty on the Silverado chassis-cab 4500HD,
5500HD and 6500HD trucks excludes the
Allison® transmission and Transmission Control
Module (TCM). Investigate Vehicle History (IVH)
will display this as: Powertrain Ltd. Wty. (Excludes
Trans). The Allison® Transmission and TCM will
be warrantied by Allison® and will have to be
taken to an Allison® Authorized Distributor and
Dealer Location for repair or replacement.
Find an Allison® Authorized Service Facility near
you by searching the Sales + Service Locator.
Click on:
Sheet Metal: Corrosion coverage is for the first
3 years or 36,000 miles, whichever comes first.
Sheet Metal: Rust-through coverage is for the
first 6 years or 100,000 miles, whichever comes
first.

Page 32

November, 2019

Bulletin No.: 18-NA-366

Wireless Charging

5183776

The Wireless Charging system for mobile devices is
located on the storage tray on top of the center console
(Crew Cab bucket seat equipped models only).
1. The vehicle must be ON or Retained Accessory
Power (RAP) must be active.
2. Remove all objects from the charging pad.
3. Place the device, face up, against the rear
alignment rib on the charge pad.
4. The charging symbol will appear on the
infotainment screen when charging. If the device is
not charging, remove it for 3 seconds and rotate it
180 degrees.

Special Tools
The following new tools were released for the 2019
Silverado 4500HD, 5500HD and 6500HD chassis cab
medium duty trucks:

Special Tools — Tool Number and Description
Tool Number

Description

EN-52539

Holder, Fan Clutch Pulley — Engine L5D and L5P

EN-52538

Compressor, Tensioner Strut — Engine L5D

J-39197-21

T&B Flex Connector (incl. J-39197-1 x3) — Electrical for Allison Transmission

J-39197-22

0.062 AMP Male Connector (incl. J-39197-2 x3) — Electrical for Allison
Transmission

J-39197-23

280 Series Flex Connector (incl. J-39197-3 x3) — Electrical for Allison
Transmission

J-47277

4th Gen TCM Terminal Test Probe (Orange) — Electrical for Allison Transmission

GE-52582

Drain Hose (w/ Quick Connect and Valve) — Engine Cooling

DT-52713

Transfer Case 7-way Breakout Harness — Driveline

DT-52709

Pinion Seal Installer (Front) — Driveline Dana

DT-52710

Pinion Seal Installer (Rear) — Driveline Dana

PN 20-2977-2 (8-Lug, 19.5 inch Stud Kit)

Wheel Balancer Adapter — Will Ship Essential

Bulletin No.: 18-NA-366

November, 2019

Page 33

Special Tools — Tool Number and Description (cont'd)
Tool Number

Description
Special Tool Loan Program

CH-52708

Parking Brake Adjustment Tool — Brakes

CH-52707

Installer / Remover, Bushing (1.35" O.D.) — Chassis

CH-52706

Installer, 1.39" I.D. x 1.76" O.D. — Chassis

CH-52705

King Pin Bushing Service Kit — Chassis

DT-52739

Transfer Case Support Adapter — Transfer Case (Meritor)

Training Course
Training Courses — Description — Number and Course Name
Description

Number and Course Name

New Model Features

#90319.50W: 2019 Medium Duty Silverado 4500HD, 5500HD,
& 6500HD New Model Features

Version Information
Version

2

Modified

Released December 18, 2018
Revised October 22, 2019 —Added the Exhaust Aftertreatment System Component
Names and their identifiers from the Power and Signal Master Electrical Component List.

Trademark Footnotes
ACDelco® is a registered trademark of General
Motors LLC
Allison® is a registered trademark of Allison
Transmission
– Emergency Vehicle Series™ is a trademark of
Allison Transmission
– Highway Series™ is a trademark of Allison
Transmission
– Motorhome Series™ is a trademark of Allison
Transmission
– Rugged Duty Series™ is a trademark of Allison
Transmission
Android™ is a trademark of Google LLC .
Android Auto™ is a trademark of Google LLC
Apple® is a registered trademark of Apple Inc.

Bluetooth® is a registered trademark Owned by
Bluetooth SIG, Inc.
Bosch® is a registered trademark of Robert Bosch
GmbH, Germany
CarPlay™ Software Feature is a trademark of
Apple Inc.
Duramax® is a registered trademark of General
Motors LLC (United States)
Duramax™ is a trademark of General Motors LLC
Goodyear® is a registered trademark of The
Goodyear Tire & Rubber Company
Hydro-Max™ is a trademark of Robert Bosch
GmbH, Germany
LTE™ is a trademark of the European
Telecommunications Standards Institute (ETSI)
OnStar® is a registered trademark of OnStar, LLC
Speedpass+™ is a trademark of Exxon Mobil
Corporation
Wi-Fi® is the registered trademark of the Wi-Fi
Alliance

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.

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