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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.

By type

By component

By trouble code

By topic

Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
PIP4912G2020-08-10. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary Information communication provides information to the technician on vehicles that may have an intermittent high idle. If a technician has duplicated, or the customer description aligns with the speeds mentioned in the idle speed description tables, the idle speed should be considered a normal characteristic of current vehicle design.
PIP57332020-08-10. Service bulletin. ENGINE. This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
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.
17NA1662020-08-10. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:ENGINE:HARD PARTS INTERNAL/MECHANICAL. This technical bulletin provides a procedure to measure vibration and install engine mounts to correct a Rough Idle in Drive concern.
16NA3802020-08-10. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:MANIFOLD/HEADER/MUFFLER/TAIL PIPE. This informational bulletin provides a procedure on how to perform a quick test to check if the DPF is the cause of excessive soot from the tailpipe.
N192264210-022020-06-29. Service bulletin. EQUIPMENT; FUEL SYSTEM, DIESEL: PRE-HEATER; ENGINE AND ENGINE COOLING:ENGINE:DIESEL. Customer Satisfaction Program - Certain vehicles equipped with the 6.6l Duramaxdiesel engine (RPO L5P) and optional engine-block heater cord, may have a condition in which the block heater cable function was disabled. Dealers will replace the engine block heater and cord.
150601002J2020-06-22. Service bulletin. ENGINE. This technical bulletin provides a procedure to repair the valve lifter oil manifold and/or lifters to correct the customers concern of engine misfire, ticking noise and/or MIL Illuminated.
140604004G2020-06-22. Service bulletin. ENGINE. This informational bulletin explains the normal noises an engine may make when the ambient temperature outside is cold or the vehicle has sat for a few hours.
030601023D2020-06-22. Service bulletin. ENGINE. This information bulletin explains how to measure for oil consumption and possible reasons for loss of oil.
20NA0982020-06-22. Service bulletin. ENGINE; FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS. This informational bulletin explains to the tech on how to order a new fuel injector by matching the part number on the part and ordering it from the EPC.
20NA0552020-06-22. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to program the ECM to correct the customers concern.
20NA0552020-06-22. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to program the ECM to correct the customers concern.
20NA0432020-06-22. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin advises the technician to not replace the TMAP sensor, clean it using air or harsh chemicals but allow time for the sensor to thaw.
20NA0102020-06-22. Service bulletin. ENGINE AND ENGINE COOLING:COOLING SYSTEM:FAN. This technical bulletin provides a procedure to replace the cooling fan if found contacting the shroud causing the customers concern.
19NA1532020-06-22. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE; EQUIPMENT. This technical bulletin provides a procedure to replace the torque converter and inspect the front pump and the TEHCM for metal.
16NA3832020-06-22. Service bulletin. ENGINE; FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY. This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
PIP5628B2020-06-15. Service bulletin. ENGINE. This Preliminary information communicates information that will need to be provided to TAC to aid in diagnosing if a vehicle comes in with misfire and DTC Codes P0300 - P0308 and/or P050D
PIP5504D2020-06-15. Service bulletin. ENGINE AND ENGINE COOLING. 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.
PIP5684A2020-06-15. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary information communicates the use of air leak diagnostic test tool CH-52250 in addition to the information found in the service manual.
PIC5650G2020-05-11. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. 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.
PIP5719B2020-05-11. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates the possibility of dtc P12A6 with the possibility of a crank no start or extended crank concern.
PIP5719A2020-05-11. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates the possibility of dtc P12A6 with the possibility of a crank no start or extended crank concern.
150601002I2020-04-27. Service bulletin. BACK OVER PREVENTION; ENGINE. This technical bulletin provides a procedure to repair the valve lifter oil manifold and/or lifters to correct the customers concern of engine misfire, ticking noise and/or MIL Illuminated.
140604004F2020-04-27. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin explains the normal noises an engine may make when the ambient temperature outside is cold or the vehicle has sat for a few hours.
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.

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