NHTSA ID Number: 10246483
Manufacturer Communication Number: 19-NA-256
TSB/Document Date: 2023-12-09
Summary
This service bulletin provides diagnostic aid information/procedures to perform inspections to determine if the engine needs to be replaced as opposed to just internal parts for knocking, rattle, squeak and/or squeal type noises from engine.
Bulletin No.:
Service Bulletin
Date:
19-NA-256
December, 2023
INFORMATION
Subject:
Diagnostic Tips for Knocking, Rattle, Squeak and/or Squeal Type Noise from Engine –
Engine Replacement Recommendations for HFV6 Gen 1 and Gen 2
This bulletin replaces PIP5216G. Please discard PIP5216G.
Brand:
Model:
Model Year:
VIN:
to
Enclave
2008
2024
LaCrosse
2010
2019
Regal
2018
2020
ATS
2013
ATS-V
2016
CT4
2022
2024
3.6L (LF4)
CT5
2020
2024
3.0L (LGY)
CT6
2016
2020
3.0L (LGW)
3.6L (LGX)
CTS
2007
CTS V-Sport
2014
3.6L (LF3)
SRX
2007
2016
2.8L (LAU)
3.0L (LF1, LFW)
3.6L (LFX)
STS
2007
2011
3.6L (LY7, LLT)
XT5
2017
2024
3.6L (LGX)
from
to
from
3.6L (LLT, LFY)
—
—
3.0L (LF1, LFW)
3.6L (LLT,
LFX, LGX)
3.6L (LGX)
3.6L (LF4)
—
—
3.0L (LF1, LFW)
3.6L (LY7, LLT,
LFX, LGX)
XT6
2020
2024
3.6L (LGX)
XTS
2013
2019
3.6L (LF3, LFX)
Copyright 2023 General Motors
LLC. All Rights Reserved.
—
3.6L (LFX, LGX)
2019
2019
—
Page 2
Brand:
December, 2023
Model:
Model Year:
Bulletin No.: 19-NA-256
VIN:
from
to
Blazer
2019
2024
3.6L (LGX)
Camaro
2010
2024
3.6L (LLT,
LFX, LGX)
Caprice PPV
2012
2013
3.6L (LFX)
Captiva Sport
2012
2015
3.6L (LFX)
Colorado
2015
2022
3.6L (LFX, LGZ)
Equinox
2008
2017
Impala VIN W
2012
2016
3.6L (LFX)
Impala VIN 1
(including Bi-fuel)
2014
2016
3.6L (LFR, LFX)
—
to
from
—
3.0L (LFW, LF1)
3.6L (LFX)
Impala
2017
2020
3.6L (LFX)
Malibu
2008
2012
3.6L (LY7)
Traverse
2009
2024
3.6L (LLT, LFY)
Acadia
2007
2024
3.6L (LY7,
LLT, LGX)
Canyon
2015
2022
Terrain
2010
2017
3.0L (LF1, LFW)
3.6L (LFX)
G6
2008
2010
3.6L (LY7)
G8
2008
2009
Torrent
2008
AURA
2007
VUE
2008
OUTLOOK
2007
—
—
—
—
3.6L (LFX, LGZ)
3.0L (LF1, LFW)
3.6L (LY7, LLT)
—
—
—
3.0L (LFW)
3.6L (LLT)
2009
2010
3.6L (LY7)
—
—
3.6L (LY7)
3.6L (LY7, LLT)
Involved Region or Country
North America, Europe, Middle East
Condition
Some customers may comment on one or more of the following conditions:
• Knocking noise
• Seized engine
• Lower end squeak or squeal
Cause
This condition may be caused by a crankshaft main or rod bearing failure.
—
Bulletin No.: 19-NA-256
December, 2023
Page 3
1. Verify there is metal in the engine oil by removing the oil pan.
2. Remove the main or rod bearing caps:
• If the main and/or rod bearing are not the cause of the debris, refer to SI for
further diagnostics.
Correction
3961446
3961447
• If the main and/or rod bearings are found to be the cause of the debris, before
deciding whether to replace the engine or repair it, refer to the Service
Procedure below before making that determination.
Page 4
December, 2023
Bulletin No.: 19-NA-256
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.
Service Procedure
3961450
1. Inspect the oil control solenoids for metal debris.
This shows the oil filter is in by-pass and unfiltered
oil with bearing debris was pumped into the oil
lubrication galleys, throughout the engine.
3961448
3966789
2. Inspect for damage to the cam caps journals and
camshaft journals on the heads (obvious signs of
metal through the cap).
Bulletin No.: 19-NA-256
December, 2023
Page 5
3. Inspect the timing chain idler sprockets for stiffness
when turning (Should turn smooth and free).
3961451
Any of the above 3 instances would be cause to
replace the engine instead of repair.
While engine replacement at this point will be
necessary, additional inspections should also be made
for conditions:
– Sludging caused by lack of maintenance. Refer to
Service Bulletin# 16-NA-222.
– Global oil starvation caused by running the engine
very low on oil.
– Intentional abuse to the engine.
Important: If this is the case, then a call to the
Technical Assistance Center (TAC) is NOT required
prior to engine replacement.
If these conditions exist, warranty could be declined, or
feedback made on Warranty Parts Center (WPC)
inspection. Maintenance documentation should be
obtained in these instances for warranty validation.
Clearly document your findings on your repair order, fill
out the cost worksheet, and call Product Quality Center
(PQC) only if required for your dealer.
A repair and then replacement will usually be cause for
additional inspection and scrutiny that could result in
more questioning about the repair methods.
HFV6 engines are scheduled to be returned to the
WPC for inspection to verify the concern, as well as the
information provided in the repair order to support the
engine replacement.
3961452
Version
6
Modified
Released November 13, 2019
Revised January 14, 2021 – Added the 2021 Model Year to applicable Models.
Revised May 24, 2021 – Added the Blazer and CT5 models.
Revised August 20, 2021 – Added 2020-2022 XT6 (RPO LGX), 2022 CT4 (RPO LF4),
2022 Model Year to Enclave, CT5, XT5, Blazer, Camaro, Colorado, Traverse, Acadia and
Canyon and added Middle East to Involved Region or Country section.
Revised March 15, 2023 – Added the 2023 Model Year to applicable vehicles and Europe
to the Involved Region or Country section.
Revised November 29, 2023 – Added the 2024 Model Year to applicable vehicles.
Additional SI Keywords: PIP5216, PIP5216A,
PIP5216B, PIP5216C, PIP5216D, PIP5216E,
PIP5216F, PIP5216G, PIP5216H, PIP5216I, PIP5216J,
PIP5216K, PIP5216L, PIP5216M
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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TSB/Document ID: 19-NA-256
Replacement Service Bulletin Number:
MFR Communication Date: 2023-11-29
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ENGINE AND ENGINE COOLING
MFR Component System:
MFR Component Subsystem:
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