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Service bulletins for the 2021 Chevrolet Silverado

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.

1747 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Bulletins, newest first
PIT6177A2024-09-12. Service bulletin. SUSPENSION. This Preliminary information communicates an issues of the left rear leaf spring making a squeaking noise due to diesel fuel contamination that may occur during refueling after the fuel nozzle is removed from the fuel filler pipe. Dealers are to create a foam seal around the fuel filler pipe to prevent fuel from leaking onto the left spring.
23-NA-0442024-09-11. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This service bulletin provides information on AGM batteries that require less frequent charging in storage.
19-NA-2372024-09-11. Service bulletin. ENGINE. This service bulletin explains how to identify possible DEF system contamination.
PIT62202024-09-11. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates that a dealer may find the underhood beauty covers missing. The dealer is advised that these are missing by design and should not be ordered for the vehicle.
PIP59962024-09-11. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostic information for vehicles with transmission noise
PIT5509L2024-09-11. Service bulletin. SERVICE BRAKES. This Preliminary Information communication provides information to the technician on how to diagnose and repair vehicle that may have a "Check Trailer Wiring" or "Service Trailer Brake System” message on the Driver Information Center when a trailer is connected to the vehicle. Diagnostic Trouble Code C1114 set in the Chassis Control Module. Chassis Control Module has to determine the type of trailer brake system that is being used. The Chassis Control Module can be sensitive to a variety of trailer wiring issues. The technician will need to make a trailer tester using Electric Trailer Brake Magnets and 7-way trailer connector to determine if it is a vehicle or trailer issue. If the concern is not duplicated with the tester installed, the vehicle is operating correctly and the focus should be on the trailer wiring or 7 way connector.
PIC6086H2024-09-11. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides the technician with steps to resolve the issue of an oily substance that may be found on the inside windshield surface, and appears to be leaking from the rear view mirror area. Technician will remove the moisture sensor and clean the glass and mounting bracket with alcohol wipe. If the gel separates from the sensor the sensor will need to be replaced.
PIT62122024-09-11. Service bulletin. SERVICE BRAKES. This Preliminary information communicates an issue with the Hydrastar Electric Over Hydraulic trailer brake system causing a voltage spike into the trucks electrical system which is causing DTC C1114 to set.
18-NA-1502024-09-07. Service bulletin. ENGINE. This service bulletin provides information on 6.6L Duramax Possible Oil Leak Path Information.
17-NA-3742024-09-07. Service bulletin. ENGINE. This informational bulletin advises the technician of how the Soot information has changed from grams to percentage.
PIT6134B2024-09-06. Service bulletin. SERVICE BRAKES. This Preliminary information communicates an issue with premature brake pad life and engineering is working on release new pad lining material.
PIP59922024-09-06. Service bulletin. POWER TRAIN. This Preliminary information communicates the results if an in-correct P/N Stator Shaft Support was installed during a transmission repair attempt.
PIT5894C2024-09-06. Service bulletin. WHEELS. This Preliminary information communicates Some customers may comment on a vibration while driving. The cause of the condition may be that the wheel and tire assemblies require Road Force balance. Please open a Tac case and provide the following information. Check the valve stems are they pointing at each other (lined up)? What wheels is the vehicle equipped with steel or Aluminum? What brand are the tires goodyear or Continental’s? Then follow bulletin 21-NA-270 for repair information
PIT3271P2024-09-06. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician about changing the tire and wheel size on vehicles. General Motors will only support a tire calibration for tires that have been sized, tested and designed for the vehicle in question and its applications. Technician should not use the information that is provided by the antilock braking system tire size selection.
24-NA-0432024-09-06. Service bulletin. FUEL/PROPULSION SYSTEM. This bulletin advises the tech that there are extra characters on the fuel injector and to ignore the last numbers when identifying flow rate.
PIC5650L2024-09-06. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.
PIT61982024-09-06. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This Preliminary information communicates a diagnostic tip for an SES MIL at startup with DTC U0100. Dealer are to test the accessory wake up circuit to the ECM for power.
23-NA-1412024-09-06. Service bulletin. ENGINE. This informational bulletin advises the technician that the engine and related parts will be debited if found that the tech did not properly prepare the engine block from dirt and debris in bolt holes or if found that the block was damaged by the tech.
16-NA-3802024-09-06. Service bulletin. ENGINE. This service bulletin provides a diagnostic aid procedure on how to perform a quick test to check if the DPF is the cause of excessive soot from the tailpipe.
16-NA-3762024-09-05. Service bulletin. ENGINE. This informational bulletin provides information on higher than expected oil consumption.
16-NA-3722024-09-05. Service bulletin. ENGINE. This bulletin provides information on common diesel engine tick noises and how they are considered part of normal operation and no parts should be replaced for these normal operating conditions.
16-NA-2442024-09-05. Service bulletin. ENGINE. This informational bulletin provides information on Diesel Exhaust Fluid (DEF) and the proper use of the DEF system.
16-NA-2222024-09-05. Service bulletin. ENGINE. This bulletin provides information on Engine Concerns that could result from lack of scheduled maintenance, improper service or aftermarket calibrations.
09-06-04-026Y2024-09-05. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
07-06-01-016J2024-09-05. Service bulletin. ENGINE. This service bulletin provides information on Internal Engine Noise or Damage After Oil Filter Replacement.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.