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Service bulletin 21-NA-214

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 id10242114
Published by NHTSA2023-09-09
Manufacturer's number21-NA-214
Manufacturer's date2023-08-10
NHTSA componentSERVICE BRAKES, AIR; ELECTRICAL SYSTEM; POWER TRAIN; ENGINE AND ENGINE COOLING

NHTSA's summary

This technical bulletin provides repair information to correct a customer concern of Service Engine Soon Lamp being illuminated. They may also comment on multiple transmission issues including harsh or delayed shifts, slip, surge, shudder, noise, whine, growl, shake and/or vibration. As well as the exhaust brake not working or that they do not feel it. Technicians may find DTCs P2002, P2463, P2459, P144E, P0421, P0422, P0106 P20EE, P129F, P16F3, P20FF, P226D, P249D, P249E, P11CC and / or P11D5.

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

Brakes, Electrical system, Engine, Transmission and driveline

Trouble codes named

P0106, P0421, P0422, P11CC, P11D5, P129F, P144E, P16F3, P2002, P20EE, P20FF, P226D, P2459, P2463, P249D, P249E

Vehicles listed
CHEVROLET SILVERADO 25002020 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 35002020 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 25002020 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 35002020 (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.

Recalls for the same vehicles and component
20260602026-02-12. Powertrain
26V0830002026-02-12. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT:VALVES/VALVE BODY
25V7680002025-11-06. SERVICE BRAKES, HYDRAULIC:POWER ASSIST
25V3900002025-06-12. SERVICE BRAKES, HYDRAULIC:BRAKE FLUID LOW WARNING:SWITCH/SENSOR/FLOAT
20246372024-10-24. Powertrain
24V7970002024-10-24. POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT:VALVES/VALVE BODY; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE
20205052020-10-23. Powertrain
20V6500002020-10-22. POWER TRAIN:DRIVELINE:DRIVESHAFT
20200792020-02-27. Brakes
20V1160002020-02-27. SERVICE BRAKES, HYDRAULIC:FOUNDATION COMPONENTS:DISC:CALIPER

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
N2525155902026-01-27. Service campaign. Certain vehicles listed above, may have a condition in which the body-to-chassis ground strap may be corroded. Dealers will replace the ground strap.
24-NA-2622025-12-03. Service bulletin. This bulletin helps aid the tech in possible 10L100 transmission noise that may be normal or abnormal depending on the concern noted.
00-06-01-026R2025-12-03. Service bulletin. This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
23-NA-1702025-10-25. Service bulletin. This bulletin advises the tech to inspect deeper into what may be to main cause of an engine failure.
23-NA-1532025-10-25. Service bulletin. The service bulletin advises the tech of a normal transmission shift condition and the delay in throttle response when the throttle plate is opened rapidly and advises the customer that it is normal for the delay.
23-NA-2012025-10-21. 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.
24-NA-2412025-10-16. Service bulletin. This informational bulletin advises the technician of a part number change for long block engines used in the trucks noted.
22-NA-0802025-10-16. Service bulletin. This technical bulletin provides a procedure to replace the camshaft actuator magnet to correct customer concerns of engine related shudder.
N242454441 -032025-10-09. Service campaign. Certain vehicles listed above, may have a condition where the transmission control valve has worn, resulting in a gradual loss of pressure within the valve. The effects can cause harsh shifting, setting a service engine soon message, reduced engine performance or P0747 diagnostic trouble code. Dealers are to install a new control valve body. The repairs will be made at no charge to the customer.
22-NA-1612025-09-27. Service bulletin. This informational bulletin provides information for dealers/technicians on power folding mirrors do not fold at the same speed.