21-NA-142

Service Bulletin
Bulletin No.:
21-NA-142
Date:
April, 2022
TECHNICAL
Subject:
Front Brake Grind/Groan Noise After Sitting Overnight
This bulletin replaces PIT5805B. Please discard PIT5805B.
Brand:
Model:
Buick
Enclave
Cadillac
Chevrolet
GMC
XT5
XT6
Model Year:
from
2020
2021
Colorado
2021
Traverse
2020
Canyon
VIN and DATE Breakpoints:
from
Engine:
Transmission:
All
All
to
5GAERBKW8LJ296460
2021
Blazer
Acadia
to
2022
1GNERKKW5LJ296020
2021
Involved Region or Country
North America, Russia, Middle East, Palestine, Japan, South Korea, Bolivia, Ecuador,
Chile, Colombia, Peru, GM Korea, Uzbekistan.
Additional Options (RPOs)
Condition
Some customers may comment on hearing a brake noise on the first few stops. They may
describe it as a grind/groan sound, and it may feel like ABS is active, but it is not.
Cause
The cause of the condition may be the front disc brake pad material.
Note: A revised pad material is being developed to address this noise concern and
should be available in the September/October timeframe. If the customer is not satisfied
with waiting for the new pads, follow the Correction below.
Correction
Verify the condition is present and check the pad number stamp on the top edge of
the pad.
If you see GA9130 or GA9140, and this is the first visit,
1. Replace the front disc brake pads with the parts listed below, refer to Front Disc
Brake Pads Replacement in the Service Manual
2. Scuff the rotors.
3. Perform the Brake Pad and Rotor Burnishing procedure. Refer to Brake Pad and
Rotor Burnishing in the Service Manual Complete a minimum of 20 stop events.
If you see GA9140, and this is a second visit,
1. Replace the front disc brake pads with the parts listed below, refer to Front Disc
Brake Pads Replacement in the Service Manual
2. Scuff the rotors.
3. Perform the Brake Pad and Rotor Burnishing procedure. Refer to Brake Pad and
Rotor Burnishing in the Service Manual Complete a minimum of 20 stop events.
Copyright 2022 General Motors LLC. All Rights Reserved.
Page 2
April, 2022
Bulletin No.: 21-NA-142
Parts Information
Causal
Part
Description
Part
Number
Pad Kit-Frt
Disc Brk
85520396
(Acadia,
Blazer,
Enclave,
Traverse,
XT5
and XT6
X
Pad Kit-Frt
Disc Brk
Qty
1
85139417
(Colorado,
Canyon)
Warranty Information
Repairs made for the specific concern within this
bulletin will be covered for a period of 24 months or
24,000 miles or 40,000 km, whichever occurs first.
Labor Operation
2486258*
Description
Base Labor Time
Front Disc Brake Pads Replacement and Scuff Both Front
Rotors
Canyon/Colorado – 1.1 hr
Enclave – 1.1 hr
Traverse – 1.1 hr
Blazer – 1.1 hr
Acadia – 1.2 hr
XT5 – 1.1 hr
XT6 – 1.6 hr
*This is a unique Labor Operation for Bulletin use only.
Version
6
Modified
Released June 21, 2021
Revised June 30, 2021 – Replaced LTG Labor Operation with Unique Bulletin Labor
Operation
Revised July 13, 2021 – Updated Parts Information with New Replacement Service Part
# 85520396.
Revised January 27, 2022 – Updated Breakpoints
Revised March 09, 2022 – Changed Blazer End Breakpoint from Date to VIN.
Revised April 14, 2022 – Added Note to Cause, Updated Correction, Increased Labor
Time and Replaced Labor Operation Number.
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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