22-NA-223

Bulletin No.:
Service Bulletin
Date:
22-NA-223
November, 2023
INFORMATION
Subject:
Information on Clicking and/or Chattering Noise Coming From the Rear of the Vehicle
While Making Tight Turns
Brand:
Chevrolet
Model Year:
Model:
VIN:
from
to
Engine:
from
to
3500/4500 Medium
Duty (LCF)
2016
2024
L96/L8T
3500/4500 Medium
Duty (LCF)
2020
2024
4HK1
4500HD/4500XD
Medium Duty (LCF)
2017
2024
4HK1
5500HD/5500XD
Medium Duty (LCF)
2017
2024
4HK1
6500XD Medium
Duty (LCF)
2019
2024
4HK1/LCB
Transmission:
Involved Region or
Country
North America
Additional Options (RPOs)
G86: AXLE-LIMITED SLIP
Condition
Some customers with N-series vehicles may comment that an audible clicking or chattering noise
coming from the rear of the vehicle while making tight turns.
Cause
This condition may be caused by incorrect axle fluid having been used during the last scheduled
maintenance or in a previous repair.
– The condition can also result from delayed or skipped maintenance resulting in degradation of
axle fluid.
Copyright 2023 General Motors LLC. All Rights Reserved.
Page 2
November, 2023
Bulletin No.: 22-NA-223
Information
6182582
Refer to the graphic above to identify a limited slip differential or check the vehicle build in IVH
(Investigate vehicle History) for Option Code G86.
– LSD Stamp Codes
• B7
• D0
• D8
• D9
• H0
• H9
To resolve this problem, take the following steps/actions.
1. Replace the differential gear oil with a commercially-available gear oil (SAE80W-90 GL-5,
SAE90 GL-5) and add 20oz of limited slip differential lubricant additive (P/N 88900330
(quantity of five (5), 4oz bottles). Refer to Fluid and Lubricant Recommendations in SI.
2. Road test the vehicle for at least 10 miles by making eight to ten tight left and right turns,
such as going around a corner, to ensure the limited slip is activated and to determine if
there is no longer any audible clicking or chattering noise coming from the rear of the
vehicle during tight turns.
3. If the condition persists, technicians are to call the Technical Assistance Center (TAC)
Important: Service agents must comply with all
International, Federal, State, Provincial, and/or
Local laws applicable to the activities it performs
under this bulletin, including but not limited to
handling, deploying, preparing, classifying,
packaging, marking, labeling, and shipping
dangerous goods. In the event of a conflict between
the procedures set forth in this bulletin and the
laws that apply to your dealership, you must follow
those applicable laws.
Version
2
Modified
Released November 02, 2022
Revised November 16, 2023 – Added 2024 Model Year and Engine RPO’s.
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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