GENERAL MOTORS
DCS7343
URGENT - DISTRIBUTE IMMEDIATELY
Date:

October 14, 2025

Subject: N252517790 - Customer Satisfaction Program
Reaction Carrier Cracks
Models: 2025-2026 Chevrolet Colorado
2025 Chevrolet Express
2025 Chevrolet Silverado 1500
2025-2026 GMC Canyon
2025 GMC Savana
2025 GMC Sierra 1500

General Motors is Customer Satisfaction Program N252517790 today.

What Should Dealers Do: Dealers should review IVH or the Dealer Maxis reports
for open VINs in their inventory. Dealers can view the attached bulletin and it
will also be displayed in Service Information tomorrow.
The Stock VIN list of vehicles in dealer inventory is attached to this message.
Note: this list is only accurate at the time of report creation and all VINs should
be validated in IVH prior to repair.
For dealers with involved vehicles, a listing has been prepared and will be
available through GM Global Connect Maxis Field Action Reports or GWM Field
Action Batch Search Report. The Inventory tab of the dealer reports will contain
VINs that apply to this field action. This information is intended to assist dealers
with the PROMPT COMPLETION of these vehicles. The Customer In-Service
tab will contain customer names and addresses from Motor Vehicle Registration
Records. The use of such motor vehicle registration data for any purpose other
than follow-up necessary to complete this field action may be a violation of law in
several states.

END OF MESSAGE

Customer Satisfaction Program
N252517790 Reaction Carrier Cracks
Release Date:
Attention:

October 2025

Revision:

00

Investigate Vehicle History (IVH) in the GM Global Warranty Management system MUST always
be checked to confirm vehicle involvement and MUST be in OPEN status prior to beginning any
required inspections and/or repairs. DO NOT use Service Information with VIN search, as it will
not verify the VIN eligibility for field actions.
This program is in effect until October 31, 2027.
Model Year

Make
Chevrolet
Chevrolet
Chevrolet
GMC
GMC
GMC

Model

From
2025
2025
2025
2025
2025
2025

Colorado
Express
Silverado 1500
Canyon
Savana
Sierra 1500

To
2026
2025
2025
2026
2025
2025

Investigate Vehicle History (IVH) in the GM Global Warranty Management system MUST always be checked to confirm
vehicle involvement and MUST be in OPEN status prior to beginning any required inspections and/or repairs. DO NOT
use Service Information with VIN search, as it will not verify the VIN eligibility for field actions.
Condition
Correction

Certain vehicles listed above, equipped with 8L80 or 8L90 Transmissions, may have a condition in which
the reaction carrier cracks.
Dealers are to replace the reaction carrier.

Parts – Silverado/Sierra
Quantity
1
2
2
1
1
1
1
1
1
As Req’d

Part Name
CARRIER ASM - REACTION
BOLT, PARK PAWL ACTUATOR BRACKET
BOLT, SENSOR
SEAL, TRANS FLUID CLR
CLAMP, PROP SHF SLIP YOKE BOOT (1 PIECE DRIVESHAFT)
CLAMP, PROP SHF SLIP YOKE BOOT (2 PIECE DRIVESHAFT)
GASKET, CTLTC CONV
CLAMP, TRFER CASE FRT OUTPUT SHF BOOT
GASKET/TRFER CASE ADAP
DEXRON HP

Part No.
24059373
11547864
11548404
85628205
84576034
26064275
84407373
84308104
86816628
19417577 (US)
19418066 (CAN)

Parts – Colorado/Canyon
Quantity
1
2
2
1
1
1
1
1
2
1
1
1
As Req’d

Part Name
CARRIER ASM - REACTION
BOLT, PARK PAWL ACTUATOR BRACKET
BOLT, SENSOR
CLAMP, TRFER CASE FRT OUTPUT SHF BOOT
CLAMP, TRFER CASE FRT OUTPUT SHF BOOT
CLAMP, PROP SHF SLIP YOKE BOOT
GASKET/TRFER CASE ADAP
GASKET, CTLTC CONV
SEAL, TRANS FLUID CLR PIPE
SEAL, TRANS FLUID CLR
MOUNT, TRANS (w/ 4WD)
MOUNT, TRANS (w/ 2WD)
DEXRON HP

Part No.
24059373
11547864
11548404
84308104
84124171
84576034
86816628
84407373
85628209
85628205
84653921
84653922
19417577 (US)
19418066 (CAN)

Parts – Savana/Express
Quantity
1

Part Name
CARRIER ASM - REACTION

Part No.
24059373
Page 1 of 8

Customer Satisfaction Program
N252517790 Reaction Carrier Cracks
2
2
1
2
4
2
2
2
As Req’d

BOLT, PARK PAWL ACTUATOR BRACKET
BOLT, SENSOR
SEAL, EXH MANIF PIPE (DONUT STYLE)
CLAMP, PROP SHF SLIP YOKE BOOT
BOLT, RR PROP SHF (M5/16-24X1.3)
RETAINER, RR PROP SHF FOR VEHICLES WITH 35MM U-JOINT
RETAINER, RR PROP SHF FOR VEHICLES WITH 30MM U-JOINT
SEAL, TRANS FLUID CLR PIPE FTG (O RING)
DEXRON HP

11547864
11548404
20987829
85573142
11548472
23170499
23107857
12650609
19417577 (US)
19418066 (CAN)

Reminder: Parts may be removed from SPRINT and Retail Inventory Management (RIM) and be non-returnable.
Dealers should review the affected parts to confirm RIM managed status. Parts may have quantity limiters in effect.
There are a small number of vehicles anticipated that will need this fix. Due to limited initial parts availability, dealers
are encouraged not to order these parts for use as shelf stock.
Warranty Information
Labor
Operation
9108063

Description
Reaction Carrier Replacement
Colorado/Canyon
2WD
4WD
Silverado/Sierra
2WD
4WD
Express/Savana

Labor
Time

Trans.
Type
ZFAT

Net
Item
N/A

6.8
8.1
6.1
8.0
5.5

Service Procedure
1.

Remove the Transmission from the vehicle and mount to DT-48989 Transmission Holding Fixture. Refer to
Automatic Transmission Removal and Installation in SI for Colorado/Canyon and Silverado/Sierra. Refer to
Transmission Replacement in SI for Express/Savana.

4119366
Note: The fluid pan gasket is reusable. Inspect the gasket to determine if it can be reused. If the gasket is damaged in
any way, it should be replaced.
2.

Remove the fluid pan bolts (1) and remove the fluid pan and gasket from the transmission. The fluid filter does not
need to be removed but may retain fluid.

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Customer Satisfaction Program
N252517790 Reaction Carrier Cracks

6099878
3.

Remove the Automatic Transmission Fluid Pump as indicated above. Refer to Automatic Transmission Fluid Pump
Replacement in SI.

4119602
4.

Remove and discard the two Park Pawl Actuator Bracket Bolts (1).

5.

Move the park pawl (2) away from the output carrier assembly gear.

4121123
6.

Remove and discard the two Output Speed Sensor wiring harness bolts (3).

7.

Position the Transmission Output Speed Sensor (4) and Clutch Input Speed Sensor (5) outside of the access holes.

Page 3 of 8

Customer Satisfaction Program
N252517790 Reaction Carrier Cracks

4121125
8.

Turn the transmission vertically and remove the 6 Case Extension Bolts.

9.

Carefully remove the Case Extension Assembly and Extension Seal (6).

4121151
10. Remove the Output Shaft Bearing and note the orientation.

4119614
11. Remove the Output Shaft.

4121181
12. Remove the Output Sun Gear Thrust Bearing.
Page 4 of 8

Customer Satisfaction Program
N252517790 Reaction Carrier Cracks

4121157
13. Remove the Output Sun Gear.

4121116
14. Remove the Output Carrier Assembly and the Reaction Carrier Assembly.
15. Install a new Reaction Carrier. Refer to Reaction Carrier Overhaul in SI.
16. Reverse steps above to reassemble the carrier assemblies into the Transmission, up to the point in which the output
shaft is installed.

4121186
17. Install the Output Shaft Bearing into the case extension assembly. It may be helpful to apply a small amount of
Transgel between the Output Shaft Bearing and the Case Extension bearing pocket (7).

4121125
18. Install the Case Extension Seal (6). Ensure the transmission is completely vertical and carefully install the Case
Extension assembly. Verify the Output Shaft Bearing has remained in place.
Page 5 of 8

Customer Satisfaction Program
N252517790 Reaction Carrier Cracks
19. Verify the extension fits flush to the seal/case and that the output shaft can be turned with the park pawl disengaged.
Install the 6 case extension bolts. Refer to Case Extension Assembly Installation in SI.

4121123
20. Turn the Transmission horizontally and install the Transmission Output Speed Sensor (4) and Clutch Input Speed
Sensor (5) into their appropriate positions.
21. Install two NEW speed sensor bolts (3). Tighten the bolts a first pass to 4 Nm (35 lb in). Tighten the bolts a final
pass to 45 degrees.

4119602
22. Install the Park Pawl (2) into the Output Carrier Assembly Gear and secure the Park Pawl Bracket using 2 NEW
Park Pawl Actuator Bracket Bolts (1). Tighten the bolts to 40 Nm (30 lb ft). Verify the Park Pawl functions as
designed, and that the pawl locks into the output carrier when the transmission is placed in park.
23. Install the Transmission Fluid Pan and gasket. Refer to Automatic Transmission Fluid, Pan, and/or Filter
Replacement in SI.
24. Install the Transmission into the vehicle. Refer to Automatic Transmission Removal and Installation in SI for
Colorado/Canyon and Silverado/Sierra. Refer to Transmission Replacement in SI for Express/Savana.
25. Fill the transmission to the proper level with NEW transmission fluid. Refer to Transmission Fluid Level and Condition
Check in SI.
26. Verify the transmission shifts and functions as designed.
Dealer Responsibility
All new, used, GM Certified Pre-Owned (CPO), courtesy transportation vehicles, dealer shuttle vehicles, CarBravo, etc.
in dealers' possession and subject to this field action 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 Pre-Owned (CPO) vehicles currently in the dealers’ inventory within the SHIFT Digital system 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 SHIFT Digital system, or once again be used in the Courtesy Transportation Program.
Page 6 of 8

Customer Satisfaction Program
N252517790 Reaction Carrier Cracks
Dealers are to service all vehicles subject to this program at no charge to customers, regardless of mileage, age of vehicle,
or ownership, through the end date as noted in the Attention box. Customers who have recently purchased vehicles sold
from your vehicle inventory, and for which there is no customer information indicated on the involved vehicle listing, are
to be contacted by the dealer. Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is provided in this bulletin for your use in contacting customers.
Program follow-up cards should not be used for this purpose, since the customer may not as yet have received the
notification letter.
In summary, whenever a vehicle subject to this program enters your vehicle inventory or is in your facility for service
through the end date as noted in the Attention box, you must take the steps necessary to be sure the program correction
has been made before selling or releasing the vehicle.
Dealer Reports – For USA
For dealers with involved vehicles, a listing has been prepared and will be available through GM Global Connect Maxis
Field Action Reports or GWM Field Action Batch Search Report. The Inventory tab of the dealer reports will contain
VINs that apply to this field action. This information is intended to assist dealers with the PROMPT COMPLETION of
these vehicles. The Customer In-Service tab will contain customer names and addresses from Motor Vehicle
Registration Records. The use of such motor vehicle registration data for any purpose other than follow-up necessary
to complete this field action may be a violation of law in several states.
Courtesy Transportation
USA - For repairs covered under this Field Action, Courtesy Transportation can be made available ONLY if the
customer/vehicle qualify for Courtesy Transportation per Bulletin 07-00-89-037.
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 for courtesy
transportation program details. Refer to the most current Home Office Letter (YYYY-604) on the Courtesy
Transportation Program for details.
Customer Notification
USA & Canada - General Motors will notify customers of this program on their vehicle (see copy of sample 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

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Customer Satisfaction Program
N252517790 Reaction Carrier Cracks

This notice applies to your vehicle, VIN: ________________________________
Dear General Motors Customer:
We have learned that your GM vehicle may have a condition in which the transmission reaction carrier cracks.
Your satisfaction with your vehicle is very important to us, so we are announcing a program to prevent this condition or,
if it has occurred, to fix it.
What We Will Do: Your GM dealer will replace your transmission reaction carrier. This service will be performed for
you at no charge until October 31, 2027. After that, any applicable warranty will apply.
What You Should Do: To limit any possible inconvenience, we recommend that you contact your dealer as soon as
possible to schedule an appointment for this repair. By scheduling an appointment, your dealer can ensure that the
necessary parts will be available on your scheduled appointment date.
You may schedule your vehicle for repair using the QR code below. For more information about your vehicle, or if you
have questions or concerns that your dealer is unable to resolve, please visit gm.com/service. You can also use your
preferred voice assistant (for example, “Please go to GM.com”), or call the Buick, Chevrolet or GMC Customer
Assistance Center at 1-866-467-9700. For Cadillac, please call 1-800-333-4223.
For the hearing or speech impaired, please contact our Customer Assistance Center using the Telecommunication
Relay Service by dialing 711 then providing the appropriate Customer Assistance Center number for your vehicle.
We truly appreciate you taking the time to remedy your vehicle as we know your time is valuable. We want you to know
that we will do our best, throughout your ownership experience, to ensure that your GM vehicle provides you many
miles of enjoyable driving.
Neelie O’Connor
Global Executive Director
Customer Experience Operations
Scan here to
locate a dealer.

N252517790

Page 8 of 8