22-NA-015

Bulletin No.:
Service Bulletin
Date:
22-NA-015
September, 2023
INFORMATION
Subject:
Diagnostic Tips on GDS Graphing after Road-Test, for Shake and/or Shudder During
Steady and/or Light Throttle Acceleration Between 25 and 50 MPH (40 and 80 KM/H) at
Steady Speed, and Deceleration at approximately 15 MPH (24 KM/H).
Brand:
Model:
Cadillac
to
Escalade Models
2021
2024
Silverado 1500
2020
2021
2022
2022
Silverado 1500 LTD
(RPO J21, VIN Digit
5 = W / Y)
Chevrolet
Silverado 1500 New
(RPO J22, VIN Digit
5 = A / D)
Silverado 1500
Suburban
Tahoe
Sierra 1500
Sierra 1500 Limited
(RPO J21, VIN Digit
5 = 8 / 9)
GMC
Model Year:
from
Sierra 1500 New
(RPO J22, VIN Digit
5 = H / U)
VIN:
from
to
Engine:
Transmission:
L84, L87
MQB, MQC, MHS,
MHO, MHT, MI2
2023
2021
2024
2020
2021
2022
2022
Sierra 1500
2023
Yukon Models
2021
2024
Involved Region or Country
North America, Australia, New Zealand, Europe, Uzbekistan, Middle East, Israel,
Argentina (Mercosur), Brazil (Mercosur), Bolivia (West), Chile (West), Colombia (West),
Ecuador (West), Paraguay (West), Peru (West), Uruguay (West)
Condition
Some customers may comment of a shudder, shake, vibration from approximately 25 –
50 mph (40-80 km/h) while under steady to lightly accelerating throttle.
Cause
This condition may be caused by various transmission and engine concerns. See the
Diagnostic Tips below.
– Check for Transmission and Engine related DTC’s. Resolve any DTC’s before and
reevaluate the vehicle before proceeding.
Correction
Diagnostic Tips Test Drive
The customers vehicle should be test driven in an effort to duplicate the condition. Details
of vehicle speed, driving conditions and throttle input may need to be discussed with the
customer. Some normal shudder, shake, vibration or growl can be expected in low speed,
light throttle applications as the vehicle may be going in and out for Dynamic Fuel
Management (DFM). DFM can be turned off for a test drive by shifting the transmission
into Manual Range “L9”. Driving a like vehicle under the same conditions may help
determine if the vehicle is operating like other vehicles and should be considered
characteristic of design.
Copyright 2023 General Motors LLC. All Rights Reserved.
Page 2
September, 2023
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.
Bulletin No.: 22-NA-015
Diagnostic Tip Engine Related Shudder – 22–
NA–080 Camshaft Actuator
Diagnostic Tips Engine Performance
⇒ Diagnostic Tip Related Shudder: 21–NA-207
5975002
5975000
1. Engine Speed
2. Engine Torque
3. Vibration Felt after Engine Refuel, Should be in
Reduced Firing Fraction
4. Pedal
5. Transmission Input Shaft Speed (ISS)
Diagnostic Tip Closed Throttle Shudder – TSB
21-NA-207: 2021 Silverado Sierra 5.3 (L84) 10 Speed
(MQB) only.
The condition is only present at 0% throttle during a
coast event at approximately 15 mph (24 km/h). Note
the engine RPM and torque oscillations at engine refuel
points.
1. Torque
2. Engine Speed
3. Transmission ISS
4. Pedal
Record a GDS session log and monitor engine speed,
transmission input speed and engine torque. If engine
torque is larger than +- 25 Nm while no gear shift is
active, and throttle is relatively constant the issue most
likely lies within the engine.
Observe the large variation in engine torque while
engine speed and Transmission ISS follow each other
more closely. Although this feels like shudder to the
customer it is most likely an engine related concern.
Bulletin No.: 22-NA-015
September, 2023
Diagnostic Tips TCC Solenoid – Valve Body
Page 3
3. Transmission ISS
4. TCC Pressure
• Shudder condition is present in Drive “D” but NOT
present in Manual “L9”
• Throttle would typically be less than 10% and
engine torque less than 100 Nm
• TCC slip speed will be 0 or near 0
• TCC pressure command will remain at 100 kPa
The valve body should be replaced.
Diagnostic Tip TCC Shudder – Torque
Converter
Note: This data should only be collected when driving
the vehicle in manual 9th gear so dynamic fuel
management is disabled.
5975003
1.
2.
3.
•
Torque
Engine Speed
Transmission ISS
The shudder condition is present both in Drive “D”
or Manual “L9”.
• Typically occurs at less than 15,000 miles
(24,000 km)
• Transmission ISS follows engine speed
• Relatively consistent engine torque. <+- 25 Nm
Engine torque remains relatively flat while engine
speed rises and falls. The valve body should be
replaced.
Diagnostic Tip TCC Solenoid (Drift) –
Valve Body
5975007
Note: A slight vibration that can only be felt when
dynamic fuel management is active should be deemed
normal characteristic and engine and transmission
components should not be replaced.
1.
2.
3.
4.
•
•
•
5975005
1. Torque
2. Engine Speed
Torque
Engine Speed
Transmission ISS
Pedal
TCC pressure control is steady
TCC slip is elevated
Engine RPM will increase at the shudder point
while Transmission ISS remains steady
• Engine torque remains relatively steady during the
shudder event
• Throttle angle remains steady during the shudder
event
The torque converter should be replaced.
Note: Warranty claim reviews indicate that when the
torque converter is replaced for shudder that vehicle
often returns for additional engine or transmission
repairs. In most cases the torque converter is not the
cause of the shudder.
Page 4
September, 2023
Bulletin No.: 22-NA-015
Diagnostic Tip Engine Related Shudder - Fuel
Injectors
6124137
1.
2.
3.
4.
•
•
•
Torque
Engine Speed
Transmission ISS
TPS
Engine RPM is erratic
Throttle is fairly steady/constant
Magnitude of RPM and TPS signal is relatively
small
• Engine RPM will not be in sinewave pattern. The
issue is possibly related to one or more fuel
injector.
Version
5
Modified
Released January 27, 2022
Revised March 21, 2022 - Revised Subject, Added Additional Countries, Change Turbine
Speed to Transmission Input Shaft Speed.
Revised July 21, 2022 - Added Two Notes to the Diagnostic Tip TCC Shudder – Torque
Converter section and Removed PIP5794 and Added 22–NA-080, added Important
Statement and Added Fuel Injection section.
Revised January 26, 2023 - Added 2023 to Model Year and Added M12, MHO and MHT
to Transmission RPO section.
Revised September 20, 2023 - Added 2024 to 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.
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