GLOBAL SAFETY FIELD INVESTIGATIONS
DCS5640
URGENT - DISTRIBUTE IMMEDIATELY
Date:

January 12, 2021

Subject: N202321841 - Service Update
Transmission Clutch Spring Retaining Ring
Models: 2021 Chevrolet Trailblazer
Equipped with Automatic Transmission (RPO M3F)
To:

All General Motors Dealers

General Motors is releasing Service Update N202321841 today. The total
number of U.S. vehicles involved is approximately 350. Please see the
attached bulletin for details.
Global Warranty Management (GWM)
The Required Field Action section on the Investigate Vehicle History (IVH) screen will
be updated January 13, 2021 or sooner. A list of involved vehicles in dealer new
inventory is attached to this message. Please hold all warranty transactions until IVH
has been updated.
END OF MESSAGE
GLOBAL SAFETY FIELD INVESTIGATIONS

Service Update
N202321841 Transmission Clutch Spring Retaining Ring
Release Date:
Attention:

January 2021

Revision:

00

This bulletin contains an inspection procedure for vehicles that are in dealer inventory. Vehicles that
pass the inspection procedure contained in this bulletin can be sold and delivered to the customer.
Vehicles that DO NOT PASS the inspection procedure contained in this bulletin cannot be sold
or delivered to the customer. When parts become available, a revision will be made to this bulletin to
allow for the repair of these vehicles, and floor plan reimbursement will also be added for vehicles which
did not pass the inspection procedure.
Vehicles that pass this inspection procedure can be delivered and closed using the “Inspect Only
– Vehicle Passed Inspection (No Further Action Required)” labor code 9105547.
All involved vehicles that are in New and Unsold dealer inventory must be held and not delivered to
customers, dealer traded, or used for demonstration purposes until the inspection contained in this
bulletin has been performed on the vehicle.
This service update involves vehicles in dealer inventory only and will expire February 28, 2022.

Make
Chevrolet

Model
Trailblazer

Model Year
From
To
2021
2021

RPO
M3F

Description
Automatic Transmission, 9T4X

This inspection procedure should be performed on vehicles in dealer inventory only. Involved vehicles are marked “open”
on the Investigate Vehicle History screen 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

Correction

On certain vehicles equipped with automatic transmissions, the clutch spring retaining ring may not be
fully seated. Vehicles with this condition may set DTC Code P0747 and the MIL light (malfunction
indicator light) will illuminate. This typically occurs at low mileage.
Dealers are to perform the inspection procedure contained within this bulletin.

Parts
No parts are required for this inspection procedure.
Warranty Information
Labor
Operation
9105547
9105548

Description
Inspect Only – Vehicle Passed Inspection (No Further Action
Required)
Inspect Only – Vehicle Did Not Pass Inspection and Will Require
Repair – claim submission will not close field action

Labor
Time
0.5

Trans.
Type
ZFAT

Net
Item
N/A

0.5

ZFAT

N/A

Important: Please select the appropriate labor code when submitting the claim. 9105547 should only be used if
the vehicle PASSED the inspection.
Note: When parts become available and the revised bulletin is released, Floor Plan Reimbursement will be
included for vehicles which did not pass the inspection procedure.

Copyright 2021 General Motors. All Rights Reserved.

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Service Update
N202321841 Transmission Clutch Spring Retaining Ring
Service Procedure
Important: This test should be performed with the engine idling and no use of the accelerator pedal (or engine revving).
1.

Start vehicle and warm up for 1 minute.

2.

Apply the parking brake before starting the test.

3.

While applying the brakes AT ALL TIMES, shift the transmission from P (park) to R (reverse), N (neutral) and to D
(drive) waiting 3 seconds between shifts.

4.

Reverse the steps from D (drive), N (neutral), R (reverse) and to P (park) waiting 3 seconds between shifts while
continuing applying the brakes.

5.

Repeat this process 30 times and look for a “shift bump” going into or coming out of D (drive).

6.

If no shift bumps are felt, no further action is required. Verify the vehicle engages in park and does NOT move or roll
with the park brake disengaged.

7.

If shift bumps are felt, engage the parking brake and hold vehicle until further instructions.

Dealer Responsibility
Dealers must take the steps necessary to ensure that the service update inspection has been made to all involved vehicles
in dealer inventory before selling or dealer-trading the vehicle, but no later than February 28, 2022.
All new, used, GM Certified Used, courtesy transportation vehicles, dealer shuttle vehicles, etc. in dealers' possession
and subject to this bulletin must be held and inspected/repaired per the service procedure of this bulletin before customers
take possession of these vehicles. Involved vehicles must be held and not delivered to customers, dealer-traded,
released to auction, used for demonstration, or any other purpose.
All GM Certified Used vehicles currently in the dealers’ inventory within the Certified Pre-Owned Inventory System
(CPOIS) will be de-certified and must be held and remedied per the service procedure in this bulletin. Upon submitting
an accepted/paid warranty transaction in the Global Warranty Management (GWM) system, the vehicle can be re-certified
for sale within the CPOIS system, or once again be used in the CTP program.
Dealer Reports
The Inventory tab of the Open Vehicle Report will contain Service Update Bulletin VINs that apply to this field action.
This information is intended to assist dealers with the PROMPT COMPLETION of these vehicles. The Customer InService tab will not contain Service Update Bulletin VIN data because the intent of a Service Update Bulletin is to not
inconvenience a customer with a special trip for service. Service Update Bulletins are to be completed when the
customer is in for a regularly scheduled visit.

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

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