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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.

By type

By component

By trouble code

By topic

Bulletins, newest first
PIP57272020-06-15. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostic tips on finding root cause of a hoot noise. If the technician confirms the hoot noise is only present while the torque converter clutch is applying the technician should advise the customer that the noise will diminish over mileage and should dissipate after 3,000 ? 4,000 miles of driving and does not pose a durability concern.
PIP5700C2020-06-15. Service bulletin. 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.
PIT5713A2020-06-15. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates an issue with the engine wiring harness shorting at the left front cylinder head causing any of the following issues: - IPC gauges sweeping while driving - Several IPC warning messages and MIL displayed - Any combination of the following DTC's: U0073 U0100 U0101 U0121 U0128 U0129 U0131 U0140 U0146 U0422 U2413 P0107 P0117 P0119 P0641 C2A07
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.
PIE05632020-06-01. Service bulletin. EQUIPMENT:MECHANICAL; ENGINE. This engineering information (EI) 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.
PIE0560A2020-06-01. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). This engineering information (EI) is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to a Service 4WD message being visible on the driver information center (DIC).
PIE0555A2020-06-01. Service bulletin. ENGINE; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This engineering information (EI) is requesting information from the field on vehicles experiencing reduced engine power. GM Engineering needs to gather information to root cause the customer concern and develop a field fix.
PI0281H2020-06-01. Service bulletin. STRUCTURE:BODY; EQUIPMENT ADAPTIVE/MOBILITY. This preliminary informational bulletin provides information to dealership personnel which may be helpful when addressing underbody component corrosion with customers.
090089002R2020-06-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This informational bulletin advises the dealers to maintain the vehicle stock on hand by doing a full inspection on the vehicles before sold (prepping) to the customer.
060089029R2020-06-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT. This informational bulletin includes information on Interior Cleaning - Instrument Panel (IP), Hard or Plastic Surfaces, Seats, Carpet, Leather, Vinyl, Fabric Cleaner, Stain Remover, Restorer - Product Availability.
060089029Q2020-06-01. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin provides information on interior cleaning products and what is offered to clean the interiors of GM vehicles.
000310003Z2020-06-01. Service bulletin. TIRES; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Warranty Administration bulletin is for information on General Motors New Vehicle Tire Warranty Program (U.S. Dealers Only).
20NA0952020-05-26. Service bulletin. STRUCTURE; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin is advising dealers to replace the grilles due to rust.
20NA0872020-05-26. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of Blank Radio Display or No Audio.
20NA0832020-05-26. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to check the oil level for correct reading and oil pressure switch is in working order.
20NA0822020-05-26. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This informational bulletin explains why more DEF is being used in diesel engines due to new emission standards.
20NA0732020-05-26. Service bulletin. SERVICE BRAKES; ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of Loss of Brake Assist, Various Messages Displayed in DIC, Brake Pedal Travel and Apply May Feel Different, DTC C0024 Set.
20NA0482020-05-26. Service bulletin. SEAT BELTS; EQUIPMENT. This technical bulletin provides repair information to correct a customer concern of hearing a rattle noise from driver or passenger seat belt.
20NA0122020-05-26. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This Technical bulletin provides service procedure information for dealers/technicians on Radio Software Version V135116 Over-the-Air Update.
19NA0762020-05-26. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of Blue Screen and Service Rear Vision System Message on Radio Display.
18NA3832020-05-26. Service bulletin. STRUCTURE. This technical bulletin provides repair information to correct a customer concern of water found in rear interior of cab due to water leak at rear sliding window.
PIT57432020-05-11. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates diagnostic tips when trying to root cause a SES MIL with DTC's B2B0D and B2B0E. Main cause is aftermarket electrical devices spliced into the ignition main fuses.
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.
PIT5195F2020-05-11. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician about vehicles that the speedometer needle appears to be inaccurate. Dealer should advise the customer the specification for speedometer needle accuracy is +/- 2 MPH at any given speed when looking straight at the needle.
PIP5647A2020-05-11. Service bulletin. FUEL SYSTEM, GASOLINE; ELECTRICAL SYSTEM. This Preliminary information communicates A vehicle may have a concern of running poor and stalling. No trouble codes may be set referencing this condition. Fuel trims around -20% may be observed on both banks. Engine oil level will be found over full and have a fuel odor. It will be found that the Engine oil is diluted with fuel. Small gas engines (SGE) May only have the engine oil level over full and have a fuel odor. It will be found that the Engine oil is diluted with fuel. This concern is caused by marshalling the vehicle around the lot before it is sold and/or short driver cycles.

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