19-NA-136

Bulletin No.:
Service Bulletin
Date:
19-NA-136
November, 2022
TECHNICAL
Subject:
Howling, Whining/Whirring, Shudder/Vibration, and/or Grinding Noise While in 4HI, 4HI
Auto and/or During Parking Lot Maneuvers in Auto Mode
Brand:
Model:
Cadillac
Chevrolet
to
Escalade
2015
2023
Colorado
2015
2022
Silverado
2014
2018
Silverado 1500 (New
Model – 12th VIN
Digit = 7) - 4WD
2019
2019
Silverado 1500 (New
Model)
2019
2019
Silverado 1500
2020
2021
2022
2022
Silverado 1500 - LTD
(RPO J21, VIN Digit
5 = W/Y)
Silverado 1500 - New
(RPO J22, VIN Digit
5 = A/D)
GMC
Model Year:
from
Silverado 1500
2023
2023
Silverado 2500HD/
3500HD
2019
2023
Silverado LD
2019
2019
Suburban
2015
2023
Tahoe
2015
2023
Canyon
2015
2022
Sierra
2014
2018
Sierra 1500 (New
Model)
2019
2019
Sierra 1500
2020
2021
2022
2022
Sierra 1500
2023
2023
Sierra 2500HD/
3500HD
2019
2023
Sierra Limited
2019
2019
Yukon
2015
2023
Sierra 1500 - Limited
(RPO J21, VIN Digit
5 = 8/9)
Sierra 1500 - New
(RPO J22, VIN Digit
5 = H/U)
Copyright 2022 General Motors LLC. All Rights Reserved.
VIN:
from
to
Engine:
Transmission:
Page 2
November, 2022
Bulletin No.: 19-NA-136
Involved Region or Country
North America, Middle East, Israel, Palestine, Chile, Paraguay, Uruguay, Peru, Japan,
Thailand, Australia, New Zealand, Uzbekistan, Russia, Columbia, Ecuador, GM Korea
Company, S. Korea and Europe.
Additional Options (RPOs)
NP0, NQ6, NQ7, NQF, NQG, NQH
Condition
Some customers may comment on one or more of the following conditions during parking
lot maneuvers in AUTO Mode or highway speeds in 4HI or Auto:
• Howling noise
• Whining/Whirring noise
• Shudder/Vibration
• Grinding noise
Some customers also may state that a noise can be heard in 4HI, but goes away when
switched to 2HI.
Some technicians may find the concern coming from the transfer case.
This condition may be caused by normal transfer case break-in and wear period, creating
excess contaminants in the fluid.
Cause
⇒ This may result in a customer complaint of excessive noise present with
4WD engaged and goes away when switched back to 2WD.
Perform road test to diagnose transfer case noise:
1. Place vehicle into AUTO mode, and perform low speed parking lot maneuvers,
listening for the noise description noted above.
2. Place vehicle in 4HI. From a stop under moderate acceleration, listen for any
growling, howling, whining or whirring noise.
Note: This video audio was recorded by using a picoscope microphone and was
provided as an example for what to listen for. The growling/howling/whirring noise can be
heard in the vehicle cabin during moderate acceleration in 4HI from a stop, or during
steady speed switching between 2HI and 4HI as shown in the video.
Correction
3. As shown in the video above, at approximately highway speeds (55 mph or 89 km/
h) toggle between 4HI and 2HI, and listen for the same noise description noted
(Growling, etc.).
Once the transfer case noise is confirmed, refer to Transfer Case Fluid Replacement
in SI.
Parts Information
Causal
Part
Description
Part
Number
Qty
N/A
Fluid
88865601 (in
Canada
19421425)
Refer to
Fluid
Capacities
in SI
Warranty Information
For vehicles repaired under the Powertrain coverage,
use the following labor operation. Reference the
Applicable Warranties section of Investigate Vehicle
History (IVH) for coverage information.
Labor Operation
Description
Labor Time
3080368*
Diagnostic Test and Test Drive
0.5 hr
Add
Fluid Drain and Fill
0.3 hr
*This is a unique Labor Operation for Bulletin use only.
Bulletin No.: 19-NA-136
November, 2022
Page 3
Version
4
Modified
Released June 19, 2019
Revised November 30, 2020 - Added Addition Vehicles to the Model section and
Additional Transfercase RPOs to the Additional Options (RPOs) section.
Revised February 19, 2021 - Added Model Year 2020 and 2021 to Escalade, Tahoe,
Suburban, and Yukon Models. Revised Cause statement.
Revised November 18, 2022 - Added 2022 and 2023 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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