GM Bulletin No.: 15396B
Date: October 2015

Service Bulletin
SERVICE UPDATE
SUBJECT:

Service Update for Inventory and Customer Vehicles
Harsh Shift When Starting in Low Temperatures
Expires with Base Warranty

MODELS:

2015 Cadillac Escalade, Escalade ESV
2015 Chevrolet Silverado
2015 GMC Sierra, Yukon, Yukon XL
Equipped with 6.2L Engine (L86) and 8-Speed Automatic Transmission
(M5U)

This bulletin is revised to update the Parts Information. Please discard all copies of bulletin
15396A.
This service update includes vehicles in dealer inventory and customer vehicles that return to the
dealership for any reason. This bulletin will expire at the end of the involved vehicle's New Vehicle
Limited Warranty period.
PURPOSE
This bulletin provides a service procedure to install the original design temperature-sensor wiring
harness to the valve body on certain 2015 model year Cadillac Escalade and Escalade ESV;
Chevrolet Silverado; and GMC Sierra, Yukon, and Yukon XL vehicles, equipped with a 6.2L engine
(L86) and 8-speed automatic transmission (M5U). The supplier of the transmission-wiring harness
introduced an unapproved change to the temperature sensor (thermistor), resulting in incorrect
oil-temperature readings during transition from cold to warm temperatures. This could cause a
harsh shift when starting the vehicle at temperatures below 32ºF (0ºC); however, shift quality
improves once the transmission oil warms up.
This service procedure should be completed as soon as possible on involved vehicles
currently in dealer inventory and customer vehicles that return to the dealer for any type
of service during the New Vehicle Limited Warranty coverage period.
VEHICLES INVOLVED
All involved vehicles are identified by VIN in the Global Warranty Management System –
Investigate Vehicle History Application. Dealership technicians should always check this site to
confirm vehicle involvement prior to beginning any required inspections and/or repairs. It is
important to routinely use this tool to verify eligibility because not all similar vehicles may be
involved regardless of description or option content.
Additionally, a list of involved vehicles currently in dealer inventory is available on the “Service
Update Bulletin Information” link under the “Service” tab in GM GlobalConnect (US) or attached
to the GlobalConnect message (Canada) used to release this bulletin. Customer vehicles that
Copyright 2015 General Motors. All Rights Reserved.

Page 2

October 2015

Bulletin No.: 15396B

return for service, for any reason, and are still covered under the vehicle's base warranty should
also be checked for vehicle eligibility.
PART INFORMATION
Parts required to complete this recall are to be obtained from General Motors Customer Care and
Aftersales (GMCCA). Please refer to your “involved vehicles listing” before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Part Number
24274606
19300536 or
19331925 (US)
19300537 or
19331926 (CA)

Description
TEMPERATURE SENSOR WIRING HARNESS

Quantity/Vehicle
1

FLUID A/TRANS (DEXRON HP ATF)

7

SERVICE PROCEDURE
1. Remove the transmission control wiring harness. Refer to Transmission Control Wiring
Harness Replacement in SI.
2. Install a new transmission control wiring harness. Refer to Transmission Control Wiring
Harness Replacement in SI.
WARRANTY TRANSACTION INFORMATION
Submit a transaction using the table below. All transactions should be submitted as a ZFAT
transaction type, unless noted otherwise.
Labor
Code
9101552

Description
Transmission Control Wiring Harness Replacement

Labor
Time
1.6

DEALER PROGRAM RESPONSIBILITY
Whenever a vehicle subject to this service update enters your vehicle inventory, or is in your facility
for service in the future, and the vehicle is still covered under the New Vehicle Limited Warranty,
you must take the steps necessary to be sure the service update correction has been made before
selling or releasing the vehicle.

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

Alert Details

Page 1 of 1

15396B – Service Update Bulletin - Harsh Shift When Starting in Low Temperatures - Revised Part Info
Updated Date: Oct 09, 2015 10:35 ET

GM CUSTOMER CARE AND AFTERSALES
DCS3800
URGENT - DISTRIBUTE IMMEDIATELY
Date:

October 9, 2015

Subject:

15396B – Service Update Bulletin Revised
Harsh Shift When Starting in Low Temperatures

Models:

2015 Cadillac Escalade, Escalade ESV
2015 Chevrolet Silverado
2015 GMC Sierra, Yukon, Yukon XL

To:

All Cadillac, Chevrolet and GMC Dealers

General Motors is releasing Service Update Bulletin revision 15396B today. This bulletin is revised to update the Parts Information. Please see the attached bulletin for details.
15396B Bulletin.pdf

About this Alert
Reference Number: GCUS-3-311
Published to: Home Page
Version: 1.0
Alert Type: Service Update
Original Published Date: Oct 09, 2015 10:35 ET
Expires: Dec 08, 2015 0:00 ET
Contact : [email protected]

https://dealer.autopartners.net/portal/uscontent/alerts/Pages/GCUS-3-311.aspx

10/9/2015