22-NA-232

Service Bulletin
Bulletin No.:
22-NA-232
Date:
June, 2023
INFORMATION
Subject:
Brand:
Cadillac
Diagnostic Tip for 10 Speed Oil Pump Drive Gear
Model:
Model Year:
from
to
CT6
2019
2020
CT4
2021
CT5
2020
Escalade Models
2021
Camaro
2020
2023
Silverado 1500
(New Model)
2019
2019
2020
2021
2022
2022
VIN:
from
to
Engine:
Transmission:
LM2, L84,
L87,
LSY, LGX
MHO, MHS,
MHT, MHW,
MHX, MI1, MI2,
MI4, MQA,
MQB, MQC
2023
Silverado LD
Silverado 1500
Chevrolet
Silverado 1500 LTD (RPO J21, VIN
Digit 5 = W/Y)
Silverado 1500 New (RPO J22,
VIN Digit 5 = A)
Silverado 1500
Suburban
Tahoe
Sierra 1500 (New
Model)
2023
2021
2023
2019
2019
2020
2021
2022
2022
Sierra Limited
Sierra 1500
GMC
Sierra 1500 Limited (RPO J21,
VIN Digit 5 = 8/9)
Sierra 1500 - New
(RPO J22, VIN
Digit 5 = H/U)
Sierra 1500
2023
Yukon Models
2021
Copyright 2023 General Motors LLC. All Rights Reserved.
2023
Page 2
June, 2023
Bulletin No.: 22-NA-232
Involved Region or Country
North America, Middle East, Australia, New Zealand
Condition
Some customers may comment that a whine, growl or grind noise from the vehicle.
– This noise may be present at idle and increase in intensity as engine RPM increases.
This condition typically presents itself at approximately 15,000 miles (24140 km) and
higher mileage.
Cause
This condition may be caused by the oil pump drive gears in the transmission.
Information
The noise may be present from the front of the transmission or rear of the engine:
1. Remove the transmission oil pan, valve body and transmission oil pump.
2. Inspect the oil pump driven gear on the oil pump for abnormal wear or tooth
damage.
3. Also inspect the transmission oil pump idler gear for abnormal wear, tooth damage
and side to side movement.
– If gear damage is found on both the driven and idler gear, the driven gear in the front
cover is damaged as well.
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.
Additional Information
Note: Improvements to the oil pump drive and idler
gears were made in the 2022 model year.
On 2022 and newer vehicles or vehicles that recently
had the transmission oil pump drive gears replaced.
Review the following diagnostics prior to removing the
transmission oil pan.
• Correct all Engine and Transmission
related DTC’s.
– Many DTC’s command high line pressure which
will create transmission oil pump whine noise,
which would be considered characteristic.
• Remove the Engine Drive Accessory belt to rule
out any belt driven components.
• Review of the following engine related TSB’s:
19-NA-218, 22-NA-218, PIP5900.
If gear damage and excessive side movement is not
noticed additional diagnostics should performed.
Engine noises are often heard in the transmission
bellhousing.
Note: Noise present engine running in park, in gear
foot on the brake.
6196003
Note the damage to the oil pump idler gear.
•
Possible engine related or torque converter.
Internal torque converter damage will typically
create debris in the pan.
Noise present with the engine drive accessory belt
removed.
Excessive crankshaft end play.
6196006
Note the side-to-side movement in the oil pump
idler gear.
Bulletin No.: 22-NA-232
June, 2023
Page 3
6196005
Note the damage to the oil pump driven gear.
Version
3
Modified
Released November 18, 2022
Revised January 20, 2023 - Added 2020 to CT5 and Added Addition Keywords Section.
Revised June 13, 2023 - Added 2023 to Applicable Vehicles and Updated Additional
Information section.
Additional Keywords: 10L80, 10 Speed
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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