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Service bulletins for the 2018 GMC Sierra

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.

1723 on file from NHTSA, as of 2026-10-19.

Warranty extensions
22-NA-2442024-05-30. ELECTRICAL SYSTEM; EXTERIOR LIGHTING; STRUCTURE:BODY; UNKNOWN OR OTHER; SERVICE BRAKES. This service bulletin provides information about GM Accessories - Dealer-Installed, Repaired or Replaced During Warranty Coverage Period.

A warranty extension may pay for a repair after the basic warranty has ended. Read the document for which vehicles and which repair it covers.

By type

By component

By trouble code

By topic

Bulletins, newest first
PIP61332026-09-30. Service bulletin. UNKNOWN OR OTHER. This PI was created to help address the correct repair regarding a low coolant message on the DIC
PIT5698F2026-09-30. Service bulletin. UNKNOWN OR OTHER. This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.
PIP5700H2026-09-29. Service bulletin. UNKNOWN OR OTHER. This PI communicates the proper part numbers for transmission connectors and internal harness to prevent confusion when ordering
PIP4902W2026-09-10. Service bulletin. UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIT5680B2026-07-30. Service bulletin. UNKNOWN OR OTHER. This PI provides information to repair the door water deflector which is not sealed properly allows water into the door jam/sill area.
PIT5099J2026-07-29. Service bulletin. UNKNOWN OR OTHER. PI to help diagnose A/C concern
PIT5509N2026-07-29. Service bulletin. UNKNOWN OR OTHER. This PI provides diagnostic tips for diagnosing electric trailer brakes issues.
PIT5544J2026-07-07. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates information on a hydraulic rush type noise from the power steering gear. This noise is a characteristic of the new Active Hydraulic Assist System RPO NV8 and no repairs should be made. The noise is most noticeable in the cab at idle, in park, with all accessories turned off.
PIT5509M2026-05-19. Service bulletin. UNKNOWN OR OTHER. This PI provides diagnostic tips for diagnosing electric trailer brakes issues.
PIT3271Q2026-04-07. Service bulletin. UNKNOWN OR OTHER. This preliminary information communicates information about how to determine if a wheel and tires size change is available.
PIP61042026-03-17. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.
PIP4902V2026-03-17. Service bulletin. UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIT4506J2026-02-23. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician that some owners of Heavy Duty Trucks and Utilities may ask if they can lower their tire pressures. Tire pressures being set to the "Tire and Loading Label" will ensure the safe handling and ride characteristics of the truck and should not be lowered.
PIT64832026-02-11. Service bulletin. UNKNOWN OR OTHER. This preliminary information communicates an issue with aftermarket LED headlights causing IPC warning messages and MIL along with several low speed lan DTCs.
PIT6400A2026-01-19. Service bulletin. UNKNOWN OR OTHER. This PI Communications information on an alternative product dealers can use to perform 19-NA-255: Wax Coating on Frame Peeling, Metal Shows Corrosion/Rusting due to issue with getting product from current supplier listed in the bulletin.
PIP5700G2026-01-19. Service bulletin. UNKNOWN OR OTHER. This PI communicates the proper part numbers for transmission connectors and internal harness to prevent confusion when ordering
PIP4902U2026-01-13. Service bulletin. UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIT5984A2025-12-29. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates a diagnostic tip for an issue where the starter stays engaged after the engine starts. Dealers are to suspect/monitor the crankshaft position sensor.
25-NA-1562025-12-04. Service bulletin. WHEELS. This service bulletin provides information on Tire Sidewall Irregularities.
07-08-42-006U2025-12-03. Service bulletin. EXTERIOR LIGHTING. This service bulletin provides technicians with information on available BCM calibrations to restore bulb outage detection on vehicles produced by a second stage manufacturer (Upfitter), and/or turn signals flash fast after factory box removed.
00-06-01-026R2025-12-03. Service bulletin. ENGINE. This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
PIT5214G2025-11-28. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician about vehicles that have had multiple repair attempts that are being performed on customer’s vehicles that exhibit vibration conditions without utilizing the support of General Motors Technical Assistance Center. If valid vibration frequency or Road Force Variation data has been collected and a repair attempt does not correct the customer complaint, contact General Motors Technical Assistance Center for further support. For any vehicles that remains unrepaired after being at the dealer for three days or more and a related bulletin or PI is not found, contact General Motors Technical Assistance Center for further support.
PIP5700F2025-11-03. Service bulletin. UNKNOWN OR OTHER. This PI communicates the proper part numbers for transmission connectors and internal harness to prevent confusion when ordering
23-NA-1532025-10-25. Service bulletin. ENGINE. 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.
PIP60882025-10-24. Service bulletin. UNKNOWN OR OTHER. This PI Addresses a possible solenoid wiring fault and how to inspect the build date to identify

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