GLOBAL SAFETY FIELD INVESTIGATIONS
DCS4945
URGENT - DISTRIBUTE IMMEDIATELY
Date:

January 3, 2019

Subject: N182188930 - Special Coverage
Auxiliary Transmission Cooler Line Fluid Leak
Models: 2017-2018 Chevrolet Silverado HD
2017-2018 GMC Sierra HD
Equipped with L5P (Duramax Diesel Engine)
To:

All General Motors Dealers

General Motors is releasing Special Coverage N182188930 today. The total
number of U.S. vehicles involved is approximately 123,984. Please see the
attached bulletin for details.
Customer Letter Mailing
The customer letter mailing will begin in mid-January 2019.
Global Warranty Management (GWM)
The Investigate Vehicle History (IVH) screen in the GWM system will be updated
January 3, 2019. Please hold all warranty transactions until IVH has been updated.
END OF MESSAGE
GLOBAL SAFETY FIELD INVESTIGATIONS

Special Coverage Adjustment
N182188930 Auxiliary Transmission Cooler Line Fluid Leak
Release Date:
Make
Chevrolet
GMC

January 2019

Model
Silverado HD
Sierra HD

Revision:
Model Year
From
To
2017
2018

RPO
L5P

00

Description
Engine-Diesel, 8 Cyl, 6.6l, Di, V8,
Turbo, Duramax, Gen 5, Var. 1

Involved vehicles are identified on the Applicable Warranties section in GM Global Warranty Management system. This
site should always be checked to confirm vehicle involvement prior to beginning any required inspections and/or repairs.
Condition

Special
Coverage
Adjustment

Some 2017-2018 model year Chevrolet Silverado HD and GMC Sierra HD vehicles equipped with a
Duramax Diesel engine, the transmission cooler lines may be rubbing on the front frame/bumper mount
bracket. This condition could cause the cooler lines to leak. Transmission fluid may be seen on the
ground under the front bumper. Some drivers may have difficulty selecting gears or experience
transmission slip.
This special coverage covers the condition described above for a period of 6 years or 72,000 miles
(116,000 km), whichever occurs first, from the date the vehicle was originally placed in service,
regardless of ownership.
For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after
January 3, 2019, are covered by this special coverage and must be submitted using the labor operation
codes provided with this bulletin. Claims with repair orders prior to January 3, 2019, must be submitted
to the Service Contract provider.

Correction

Vehicle owners or lessees who paid for repairs referenced in this Special Coverage (“Customers”) are
eligible for reimbursement of their reasonable and customary expenses in accordance with the
procedures specified below. The conditional right to reimbursement is provided by GM solely in the
interest of customer satisfaction and is personal to Customers. Customers may not assign and GM
does not consent to any assignment of any Customer’s right to submit reimbursement claims, or to
receive reimbursement, or any other rights granted by this Special Coverage to any third party, including
but not limited to service contract providers, and this Special Coverage is not intended to and does not
confer any third party beneficiary, subrogation or contribution rights, or any other rights to
reimbursement, against GM, whether in law, equity or otherwise, on any third parties.
Dealers are to replace the transmission cooler lines. The repairs will be made at no charge to the
customer.

Parts
Quantity
1
(As req.)
13

Part Name
Transmission Cooler Bypass Valve
Dexron VI Automatic Transmission Fluid

(As req.)
13

Dexron VI Automatic Transmission Fluid (Canada)

Part No.
84444069
88865601
Obtain Local
Equivalent EXPORT
19367328

Note: An allowance for up to 13 qts of transmission fluid is provided. Use only as much fluid per repair as is necessary to
fill the system to capacity.
Reminder: Parts may be removed from Retail Inventory Management (RIM). Dealers should review the affected parts
to confirm RIM managed status. Parts may have quantity limiters in effect.
Warranty Information
Labor
Operation
9900562
9900563

Description
Diagnostic Time Only – No Repair Required
Transmission Fluid Cooler Thermal Bypass Valve Replacement
Add: Diagnostic Time

Copyright 2019 General Motors. All Rights Reserved.

Labor
Time
0.1-0.3
3.8
0.1-0.3

Trans.
Type
ZREG
ZREG

Net
Item
N/A
N/A

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N182188930 Auxiliary Transmission Cooler Line Fluid Leak
Service Procedure

5165323

1.

2.

Determine if the Transmission Fluid Cooler Thermal Bypass Valve lines are leaking from a rub-through condition in
the area shown (or another area near the thermal bypass valve). If necessary, use a borescope to aid in pinpointing
the leak without vehicle disassembly.
•

If the lines exhibit a rub-through condition and are leaking, proceed to step 2.

•

If the lines do not exhibit a rub-through condition (or are leaking from a non-rub-through condition) no further
action is required. Any further repairs and/or diagnosis are not covered under this special coverage.

Replace the Transmission Fluid Cooler Thermal Bypass Valve. Refer to Transmission Fluid Cooler Thermal Bypass
Valve Replacement (L5P With MW7) in SI.

Courtesy Transportation – For USA & Canada
Courtesy transportation is available for Customers whose vehicles are involved in a product program and still within the
warranty coverage period. See General Motors Service Policies and Procedures Manual, Sections 1.4 and 6.1.10, for
courtesy transportation program details.
Customer Notification
General Motors will notify Customers of this special coverage on their vehicle (see copy of typical Customer letter included
with this bulletin).

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 tools, equipment, 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 dealer for information on whether your
vehicle may benefit from the information.

We Support
Voluntary Technician
Certification

Page 2 of 3

N182188930 Auxiliary Transmission Cooler Line Fluid Leak
January 2019
This notice applies to your vehicle, VIN: _____________________________________
Dear General Motors Customer:
As the owner of a 2017-2018 model year Chevrolet Silverado HD or GMC Sierra HD vehicle, your satisfaction with our
product is very important to us.
This letter is intended to make you aware that on some 2017-2018 model year Chevrolet Silverado HD and GMC Sierra
HD vehicles equipped with a Duramax Diesel engine, the transmission cooler lines may be rubbing on the front
frame/bumper mount bracket. This condition could cause the cooler lines to leak. Transmission fluid may be seen on
the ground under the front bumper. Some drivers may have difficulty selecting gears or experience transmission slip.
Do not take your vehicle to your GM dealer as a result of this letter unless you believe that your vehicle has the
condition as described above.
What We Have Done: General Motors is providing owners with additional protection for the condition described above.
If this condition occurs on your 2017-2018 model year Chevrolet Silverado HD or GMC Sierra HD vehicle within 6 years
of the date your vehicle was originally placed in service or 72,000 miles (116,000 km), whichever occurs first, the
condition will be repaired for you at no charge. Diagnosis or repair for conditions other than the condition described
above is not covered under this special coverage program.
What You Should Do: If you believe that your vehicle has the condition described above, repairs and adjustments
qualifying under this special coverage must be performed by a General Motors dealer. You may want to contact your
GM dealer to find out how long they will need to have your vehicle so that you may schedule the appointment at a time
that is convenient for you. This will also allow your dealer to order parts if they are not already in stock. Keep this letter
with your other important glove box literature for future reference.
The right to submit reimbursement claims is provided by GM solely in the interest of customer satisfaction and is
personal to vehicle owners and lessees who previously paid for repairs referenced in this Special Coverage
(“Customers”). Customers may not assign and GM does not consent to any assignment of any Customer’s right
to submit reimbursement claims, or to receive reimbursement, or any other rights granted by this Special
Coverage to any third party, including but not limited to service contract providers, and this Special Coverage
is not intended to and does not confer any third party beneficiary, subrogation or contribution rights, or any
other rights to reimbursement, against GM, whether in law, equity or otherwise, on any third parties.
If you have any questions or need any assistance, please contact your dealer or the appropriate Customer Assistance
Center at the number listed below.
Division
Chevrolet
GMC
Puerto Rico – English
Puerto Rico – Español
Virgin Islands

Number
1-800-222-1020
1-800-462-8782
1-800-496-9992
1-800-496-9993
1-800-496-9994

Text Telephones (TTY)
1-800-833-2438
1-800-889-2438

We are sorry for any inconvenience you may experience; however, we have taken this action in the interest of your
continued satisfaction with our products.
Neelie O’Connor
Executive Director
North America Contact Center Operations
N182188930

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