23-NA-011

Bulletin No.:
Service Bulletin
Date:
23-NA-011
August, 2023
INFORMATION
Subject:
3.0L Duramax Possible Oil Leak Path Information
Model Year:
Brand:
Model:
Cadillac
Escalade Models
2021
Silverado 1500
2020
Suburban
2021
Tahoe
2021
Sierra 1500
2020
Yukon Models
2021
Chevrolet
GMC
from
to
2024
VIN:
from
to
Engine:
Transmission:
LM2, LZ0
Involved Region or Country
North America
Condition
Some customers may comment on an oil leak from the engine.
Information
This document is to help identify where to look for an oil leak on the 3.0 Duramax engine.
Please use the illustrations below as a guide of where to look for a potential oil leak.
These Illustrations are of a LZ0 engine; the LM2 would be similar.
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.
Copyright 2023 General Motors LLC. All Rights Reserved.
Page 2
August, 2023
Bulletin No.: 23-NA-011
Possible Oil Leak Paths
6262592
1.
2.
3.
4.
5.
6.
7.
8.
Oil Filler Neck Seal
Oil Galley Plugs
Oil Pan Drain Plug
Oil Indicator Tube Seal
Oil Pan Gasket
Engine Bed-Plate Gasket
Cylinder Head Gasket
Valve Rocker Arm Cover Gasket
6262632
1.
2.
3.
4.
5.
6.
6262643
Ghost view of the Oil Cooler Cover to reveal the seal.
Oil Pressure Sensor
Oil Temperature Sensor
Oil Galley Plug
Oil Pump Solenoid Valve Connector
Oil Filter Seal
Oil Drain Plug
Bulletin No.: 23-NA-011
August, 2023
Page 3
6262637
1.
2.
3.
4.
5.
Valve Rocker Arm Cover Gasket
Upper and Lower Turbo Return Line Seals
Cylinder Head Gasket
Lower Turbo Feed Line Seal
Tensioner Timing Chain
6262662
Upper Turbo Oil Supply Line Seal.
Page 4
August, 2023
Bulletin No.: 23-NA-011
6262659
1.
2.
3.
4.
5.
6.
Cover Timing Chain
Camshaft Sensor
Oil Gallery Plugs
Timing Chain Cover Lower Seal
Rear Crankshaft Seal
Fuel Pump Cover
1.
2.
3.
4.
5.
Oil Filler Neck Seal
Upper Oil Galley Plug
Front Crank Shaft Seal
Front Cover Seal
Lower Oil Gallery Plug
6262626
Bulletin No.: 23-NA-011
August, 2023
Version
2
Modified
Released February 06, 2023
Revised August 02, 2023 — Added the 2024 Model Year.
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.
Page 5
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