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Service bulletin 20NA142

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10181693
Published by NHTSA2020-10-26
Manufacturer's number20NA142
Manufacturer's date2020-09-09
NHTSA componentEQUIPMENT; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT

NHTSA's summary

This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Equipment and accessories, Transmission and driveline, Automatic transmission

Vehicles listed
CHEVROLET EXPRESS2015, 2016, 2017, 2018, 2019
CHEVROLET SILVERADO 15002015, 2016, 2017, 2018, 2019 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 25002015, 2016, 2017, 2018, 2019 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 35002015, 2016, 2017, 2018, 2019 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 45002019 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SUBURBAN2015, 2016, 2017, 2018, 2019
GMC SAVANA2015, 2016, 2017, 2018, 2019
GMC SIERRA 15002015, 2016, 2017, 2018, 2019 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 25002015, 2016, 2017, 2018, 2019 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 35002015, 2016, 2017, 2018, 2019 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA DENALI2015, 2016, 2017, 2018, 2019 (the catalog's model; the bulletin names a series or trim of it)
GMC YUKON2015, 2016, 2017, 2018, 2019
GMC YUKON XL2015, 2016, 2017, 2018, 2019

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
14V1520002014-03-31. POWER TRAIN:AUTOMATIC TRANSMISSION:COOLING UNIT AND LINES

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
PI0690B2024-04-29. Service bulletin. MIL Illuminated.
148762023-12-18. Service bulletin. 8-speed Transmission Harsh Shift
140730001B2023-12-11. Service bulletin. Information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts
1407300012023-12-11. Service bulletin. Information on Transmission Adaptive Functions
17-NA-0662023-07-25. Service bulletin. This service bulletin provides information for automatic transmission Oil Cooler Flush and flow test.
PIP5853C2023-05-15. Service bulletin. This PI communicates to dealers and technicians a possible diode issue in the TCCM, and how to properly diagnose for a diode issue.
16-NA-1302023-03-08. Service bulletin. This service bulletin provides information for after installation of a replacement upper valve body, the transmission may have no Reverse and no 2nd gear.
PIP5621C2022-10-17. Service bulletin. This Preliminary information communicates to the dealer technician that TAC recommends the utilization of the GDS2 software to aid in diagnosing automatic transmission concerns. TAC is requesting the GDS2 session logs be sent in before the dealer contacts TAC.
N1821953802022-05-31. Service bulletin. Service Update. Certain vehicles equipped with a 10-speed transmission may have a condition where the downshift becomes firm after extended highway driving.
183672022-05-31. Service bulletin. Customer Satisfaction. Certain vehicles, equipped with the 10-speed automatic transmission (RPO MF6), may have a condition in which the transmission manual shaft pin was not seated properly. If the shaft pin were to migrate out of position, the driver may find they cannot shift the vehicle into any gear other than the last one selected. The customer may be unable to return the vehicle back to park, in which case they would be required to engage the parking brake to ensure the vehicle does not roll from its intended position. Dealers will replace the transmission manual shaft pin. Private Message sent to select dealers.