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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.

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By component

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Only bulletins with component: Transmission and driveline are shown. Show all

Bulletins, newest first
PIP5175D2020-08-10. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:INTERNAL:GEARS; ENGINE AND ENGINE COOLING. This Preliminary Information communication provides information to the technician about vehicles that may have a delayed engagement into drive, shudder at a launch, or the transmission is slipping when shifting into 1st, 2nd, 3rd or 4th gears. This may be due to loose stator support to pump cover bolts causing a leak at the stator support to pump cover gasket. Technician will check for the bolts to be loose. If any of the bolts are loose or the gasket is misaligned or leaking, the transmission pump cover must be replaced and the 1234 clutch plates should be inspected for being distressed and repaired as needed.
20NA1382020-08-10. Service bulletin. POWER TRAIN. This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
PIT5593B2020-06-15. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN; STEERING. This Preliminary information communicates a power steering control module calibration error that does not allow its DTC's to transition to history and they always stay current, which can mislead a technician diagnosis. Dealers are to reprogram the power steering control module with updated calibration which will allow DTC's to transition to history if the issue that caused the DTC(s) are now longer present.
PIP5429A2020-06-15. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This Preliminary Information communication advises the technician that the customer may experience a 2-3 slip or flare after the vehicle has been sitting for a period of time. Technician can update the Transmission Control Module if working on a model year 2007. On all other model years dealer should communicate to the customer this condition is a normal operating characteristic of their vehicle.
19NA0352020-05-26. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to validate if the parking pawl actuator is not working as intended, causing the parking pawl to engage while driving.
18NA3552020-04-27. Service bulletin. POWER TRAIN; ENGINE. This technical bulletin provides information for new transmission oil to use and a procedure for exchanging the old fluid and adding the new fluid to correct a shake/shudder during light throttle acceleration condition.
PIP5700B2020-04-13. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This Preliminary information communicates to the dealer technician that the part numbers for the internal wiring harnesses for the 8 speed RWD transmissions are not listed in the Electronic Parts Catalog. Technicians are to refer to the information provided in this document to obtain the internal wiring harness part numbers by application.
N1922656602020-02-18. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. Customer Satisfaction Program - Certain 2014-2019 model year Chevrolet Silverado and GMC Sierra vehicles equipped with a power sliding rear window (RPO A48) may have areas of high electrical resistance on the rear defroster circuit. This could be caused, in part, by mechanical stress from opening and closing the rear power window, intrusion of debris, and use of the rear defroster. Over time, this condition could generate heat that could melt the areas surrounding the circuit. In rare instances, this heat could cause a non-propagating fire, increasing the risk of property damage or injury. Dealers will replace the buss bar covers and contact cover. If the rear window or sliding glass assembly appears damaged due to an occurrence of high electrical resistance on the rear defroster circuit, they should also be replaced.
PIP5700A2020-02-10. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. This Preliminary information communicates to the dealer technician that the part numbers for the internal wiring harnesses for the 8 speed RWD transmissions are not listed in the Electronic Parts Catalog. Technicians are to refer to the information provided in this document to obtain the internal wiring harness part numbers by application.
PIP5504C2020-02-10. Service bulletin. POWER TRAIN. This Preliminary Information communication provides information and definitions to the technician about vehicles that have fishbite, chuggle, misfire, AFM disturbances or torque converter shudder/vibration concerns. Technician are advised to use PICO software to determine root cause of the concern. If torque converter shudder is confirmed technicians are referred to Torque Converter Diagnosis in SI.
PIP57002020-02-10. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. This Preliminary information communicates to the dealer technician that the part numbers for the internal wiring harnesses for the 8 speed RWD transmissions are not listed in the Electronic Parts Catalog. Technicians are to refer to the information provided in this document to obtain the internal wiring harness part numbers by application.
PIP5531A2020-02-10. Service bulletin. ENGINE; POWER TRAIN:AUTOMATIC TRANSMISSION. This Preliminary Information communication provides information to the technician on the steps need to diagnose and repair vehicles that may have stalling shudder and/or hard shifting into 1st gear or reverse vibration on launch (with excessive crankshaft end play). Technician will test to determine if the crank shaft end play is within specification 0.0015?0.0086 inch. If end play is found to be out of specification, remove engine and inspect for possible crankshaft thrust bearing and/or crankshaft for wear. Inspect thrust bearing for wear on one side and crankshaft on that "mating" surface. If the thrust bearing has three vertical channels worn off replace connecting rod bearings, main bearings, thrust bearing and crankshaft. If working on a Corvette the oil tank with lines and oil cooler are both required to be replaced if equipped
16NA0192019-12-16. Service bulletin. POWER TRAIN. Information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
19NA1532019-12-16. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This technical bulletin provides a procedure to replace the torque converter and inspect the front pump and the TEHCM for metal.
PIP5621A2019-12-09. Service bulletin. POWER TRAIN. 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.
PIE0529A2019-11-25. Service bulletin. POWER TRAIN. This engineering information bulletin ends the need for information from the field on an Intermittent No Forward and/or No Reverse While Driving condition. If this condition is encountered, refer to SI for further diagnosis.
990420002K2019-11-25. Service bulletin. POWER TRAIN. This informational bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operations.
16NA3612019-11-25. Service bulletin. POWER TRAIN. This informational bulletin explains possible normal condition of a flare from 1st to 2nd, even if the trans had been repaired for the flare and its still noticed.
16NA3382019-11-25. Service bulletin. POWER TRAIN. This Bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns.
PIE05292019-09-23. Service bulletin. POWER TRAIN. This engineering information bulletin is requesting information from the field to validate a field fix. Before contacting engineers, remove the transmission oil pan and inspect for nickel to quarter size pieces of aluminum debris in the oil pan. The 2-3-4-6-8 and 4-5-6-7-8 reverse clutch assembly and the 1-3-5-6-7 clutch assembly may be broken in several pieces.
080730026F2019-09-23. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. This informational bulletin provides information on Some vehicles may rock or move slightly forward or rearward while in Park at start up after cold soak. This condition may be accompanied by a clunk noise. This is a slight movement that is more often seen visually, rather than felt, when viewed from the outside and using the auto-start feature, if equipped.
19NA1532019-09-23. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to replace the torque converter and inspect the front pump and the TEHCM for metal.
PI1344C2019-08-19. Service bulletin. POWER TRAIN. This preliminary informational bulletin adds the 2016 model year to diagnostic tips and repair information to correct a customer concern of reduced acceleration at low speed and/or transmission slipping from a launch, DTC P0751 set.
18NA3552019-08-19. Service bulletin. POWER TRAIN. This technical bulletin provides information for new transmission oil to use and a procedure for exchanging the old fluid and adding the new fluid to correct a shake/shudder during light throttle acceleration condition.
19NA1362019-07-29. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE); EQUIPMENT ADAPTIVE/MOBILITY. This technical bulletin provides a procedure to change the diff fluid if found the cause of the customers concern.

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