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Service bulletins for the 2020 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.

1990 on file from NHTSA, as of 2026-10-19.

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Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
PIP5670B2020-02-10. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:OTHER FUEL TYPES:TURBO/SUPERCHARGER. This preliminary information communicates the part restriction for the diesel turbocharger and EGR components. Updated to provide instruction on gathering additional data.
PIP5503B2020-02-10. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV). This Preliminary information communicates to the dealer additional information on checking for the engne crankcase being overfull on oil causing an engine vibration concern. The technician is advised to inspect for contaminnants and adjust the engine oil level as needed.
PIP5689B2020-02-10. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This Preliminary information communicates to the technician to reprogram the engine control module and, if necessary, diagnose and repair P24B0.
N1922779302020-02-10. Service bulletin. ENGINE AND ENGINE COOLING. N192277930 - Service Update - Certain 2020 model year Chevrolet Silverado and GMC Sierra vehicles may, after several years of use, fracture at the yoke-to-tube friction weld joint under torsional load. If the prop shaft fractures, the vehicle will experience a loss of propulsion without warning. The customer may notice a loud bang upon fracture that will coincide with the loss of propulsion. If the prop shaft fractures while the vehicle is parked on a graded surface and the park brake is not engaged, roll away is possible. Dealer will replace prop shaft and fasteners.
N1922679902020-02-10. Service bulletin. STRUCTURE:BODY; ENGINE AND ENGINE COOLING. N192259800 - Customer Satisfaction Program - Certain 2020 vehicles vehicles, equipped with the 6.6L diesel engine (RPO L5P), may have a condition in which the adhesive attaching the heat shield to the air inlet panel may lose adhesion. Dealers are to replace the air inlet grille panel assembly.
N192266750-012020-02-10. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; ENGINE AND ENGINE COOLING. N192266750-01 - Service Update (Revised Warranty Information and Service Procedure). On certain vehicles that are equipped with a 6.6L diesel engine, may have one or more of the following conditions exist: 1.The instrument panel cluster may incorrectly display the message ?DEF Low? when a diesel engine fluid (DEF) controller internal fault is detected (DTC P20FF), instead of displaying the proper ?Service DEF System? message. 2.The customer may complain of excessive engine fan noise at a low vehicle speed. 3.Under certain conditions, the diagnostic system may set one of the following DTC?s when there is no problem with a component: (P20EE, P226D, P16F3 and P129F). Dealers are to reprogram the engine control module.
PIP5689A2020-01-21. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This Preliminary information communicates to the technician to reprogram the engine control module and, if necessary, diagnose and repair P24B0.
PIP5668B2020-01-21. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates to the dealer technician the coolant control valve is no longer on restriction.
N1922734002019-12-30. Service bulletin. EQUIPMENT; FUEL SYSTEM, GASOLINE; ENGINE. N192273400 - Service Update. Certain LD vehicles may have a condition in which the right-hand side, positive crankcase ventilation (PCV) tube may not be fully seated (loose), allowing unrestricted blow-by gases to release to the atmosphere. Customers may experience a whistling sound, or there may be an audible air leak. Disconnection of this line is monitored through the fuel trim diagnostics, and in a worst-case scenario, the customer may experience a check engine light with DTC codes P0171 and/or P0174. Dealers are to inspect and ensure the PCV tube to the right-hand rocker is fully seated and secure.
PIE05442019-12-16. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This engineering informational bulletin is requesting information on vehicles with the Service Engine Soon (SES) lamp being illuminated and DTC P1467 set.
PIE0536A2019-12-16. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ENGINE. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to oil leaking from the oil pan.
PIP56892019-12-09. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates to the technician to reprogram the engine control module
PIT5689A2019-12-09. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates that some customers may comment that after an auto-stop event the engine does not restart and to inspect the engine ground strap.
PIP5667A2019-12-09. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates the part restriction for the diesel engine air delivery and exhaust system components
PIP5686A2019-12-09. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates A vehicle may come into the dealer with a rough idle, lean running concern and/or air leak noise from the PCV system. Upon inspection the technician may find the SES lamp is illuminated and/or DTC?s P0171 and/or P0174 may be in active or stored history. This condition may be caused by an incorrectly installed foul air PCV tube or tube may be damaged
100605002H2019-11-25. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. This informational bulletin provides information on Clean Exhaust Filter See Owners Manual Now or Cleaning Exhaust Filter Keep Driving Until Message is Cleared messages Displayed on DIC, DTC P2463 May Be Set.
010601011K2019-11-25. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
18NA3612019-11-25. Service bulletin. ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to flush the cooler lines to validate if there is excessive debris in the fuel system caused by a failed part.
16NA3722019-11-25. Service bulletin. ENGINE AND ENGINE COOLING. 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.
N1922667512019-11-12. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; ENGINE AND ENGINE COOLING. N192266751 - Service Update (9 VINs moved from N192266750 due to different procedure). On certain vehicles that are equipped with a 6.6L diesel engine, may have one or more of the following conditions exist: 1.The instrument panel cluster may incorrectly display the message ?DEF Low? when a diesel engine fluid (DEF) controller internal fault is detected (DTC P20FF), instead of displaying the proper ?Service DEF System? message. 2.The customer may complain of excessive engine fan noise at a low vehicle speed. 3.Under certain conditions, the diagnostic system may set one of the following DTC?s when there is no problem with a component: (P20EE, P226D, P16F3 and P129F). Dealers are to reprogram the engine control module.
N1922667502019-11-12. Service bulletin. ENGINE AND ENGINE COOLING. N192266750 - Service Update. On certain vehicles that are equipped with a 6.6L diesel engine, may have one or more of the following conditions exist: 1.The instrument panel cluster may incorrectly display the message ?DEF Low? when a diesel engine fluid (DEF) controller internal fault is detected (DTC P20FF), instead of displaying the proper ?Service DEF System? message. 2.The customer may complain of excessive engine fan noise at a low vehicle speed. 3.Under certain conditions, the diagnostic system may set one of the following DTC?s when there is no problem with a component: (P20EE, P226D, P16F3 and P129F). Dealers are to reprogram the engine control module.
PIP5670A2019-11-12. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:GASOLINE:TURBO/SUPERCHARGER. This preliminary information communicates the part restriction for the diesel turbocharger and EGR components. Updated to provide instruction on gathering additional data.
PIP5668A2019-11-12. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates to the dealer technician the coolant control valve is on restriction.
PIP5370E2019-11-12. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary Information communication provides information to the technician that some vehicle may have an ?Exhaust Fluid Quality Poor? on the Driver Information Center or a diesel exhaust fluid warning lamp on or other exhaust fluid quality related concerns. Technician will inspect the diesel exhaust fluid for contamination. Technician should use Service Information for Contaminants in Diesel Exhaust Fluid Diagnosis and use special tool J26568 or EN50422 Diesel Exhaust Fluid Refractometer for fluid testing.
PIP5664C2019-11-12. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates to the dealer technician to refer to Service Update N192266750.

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