Service bulletin 20NA021
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.
| Type | Service bulletin |
|---|---|
| NHTSA id | 10172289 |
| Published by NHTSA | 2020-03-09 |
| Manufacturer's number | 20NA021 |
| Manufacturer's date | 2020-01-29 |
| NHTSA component | STEERING |
NHTSA's summary
This technical bulletin provides repair information to correct a customer concern of Intermittent "Service Steering Column Lock" message displayed with U0155 Set.
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
Steering
| CHEVROLET SILVERADO 1500 | 2019, 2020 (the catalog's model; the bulletin names a series or trim of it) |
|---|---|
| CHEVROLET SILVERADO 2500 | 2019, 2020 (the catalog's model; the bulletin names a series or trim of it) |
| CHEVROLET SILVERADO 3500 | 2019, 2020 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA 1500 | 2019, 2020 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA 2500 | 2019, 2020 (the catalog's model; the bulletin names a series or trim of it) |
| GMC SIERRA 3500 | 2019, 2020 (the catalog's model; the bulletin names a series or trim of it) |
Listing a model year does not mean every vehicle of it is concerned: the document says which.
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| 13-02-32-001H | 2025-05-06. Service bulletin. This service bulletin provides a procedure to flush and bleed power steering system to correct a power steering noise or fluid leak concern that is caused during extremely low temperatures. |
| 23-NA-185 | 2025-04-28. Service bulletin. This service bulletin helps diagnose/reduce possible CCND issues on Transfer Cases - Service 4WD on DIC, Intermittent Failures, Noise Concerns, Driveline/Steering Vibration/Shudder, Intermittent DTCs/MIL Illuminated, Engagement/Disengagement/Ratcheting Concerns. |
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| 16-NA-109 | 2025-02-28. Service bulletin. This service bulletin provides a procedure inspecting for excess grease or Sealant on the Exterior of the steering gear due to seeing grease or sealant on certain locations on the gear. |
| 24-NA-239 | 2025-01-30. Service bulletin. This informational bulletin provides a guide on how to diagnose and test for vibrations utilizing the PicoScope. |
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| 23-NA-201 | 2024-10-24. Service bulletin. This service bulletin advises the technician of a possible loose ground that may be causing customer concerns of Loss of Steering Assist and/or Loss of Brake Assist and Malfunction Indicator Lamp (MIL) Illuminated. |