Service bulletins for the 2020 Chevrolet 4500HD
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.
383 on file from NHTSA, as of 2026-10-19.
By type
By component
By trouble code
By topic
| 990420002L | 2021-08-09. Service bulletin. POWER TRAIN:MANUAL TRANSMISSION; POWER TRAIN:AUTOMATIC TRANSMISSION; EQUIPMENT. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation. |
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| 080730035E | 2021-08-09. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; POWER TRAIN. This bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid. |
| 21NA152 | 2021-08-09. Service bulletin. VISIBILITY:GLASS, SIDE/REAR; EQUIPMENT. This service bulletin provides information for dealers/technicians on glass ultraviolet (UV) Ray protection and tint percentage. |
| 070089037Q | 2021-08-09. Service bulletin. EQUIPMENT. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs. |
| 070089037P | 2021-08-09. Service bulletin. EQUIPMENT. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs. |
| 21NA124 | 2021-07-19. Service bulletin. FUEL SYSTEM, GASOLINE:STORAGE:EVAPORATIVE EMISSIONS:CANISTER. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set. |
| 21NA124 | 2021-07-06. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set. |
| 070089036J | 2021-06-07. Service bulletin. EQUIPMENT. This service bulletin provides information on Enhancing Field Product Reports with Digital Pictures. |
| 050308002I | 2021-06-07. Service bulletin. SUSPENSION. This service bulletin provides information to dealership personnel on diagnosis and replacement of shock absorber and strut due to fluid leak. |
| 020089002T | 2021-06-07. Service bulletin. EQUIPMENT. This service bulletin provides information for dealers/technicians on When and How to Submit a Field Product Report (FPR) (U.S. Dealers Only). |
| 000601026N | 2021-06-07. Service bulletin. ENGINE. This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage. |
| 21NA103 | 2021-05-24. Service bulletin. EQUIPMENT. This service bulletin provides information regarding Witness Marks from Panel Adjustments Made During Manufacturing and that it is considered a normal condition. |
| 21NA020 | 2021-05-24. Service bulletin. BACK OVER PREVENTION; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to correct a click type noise heard from the starter when cranking. |
| 18NA146 | 2021-05-24. Service bulletin. EQUIPMENT. This warranty administration bulletin provides policy information, proper labor operation selection and causal part identification for warranty transactions (U.S. Only). |
| 18NA073 | 2021-05-24. Service bulletin. EQUIPMENT. This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement. |
| 21NA061 | 2021-05-10. Service bulletin. ELECTRICAL SYSTEM:IGNITION:ANTI-THEFT:IMMOBILIZER/PROXIMITY:KEY/SENDER. This service bulletin provides information for dealers on Using EL-52545 When Diagnosing PEPs Transmitter Key Fobs (North America ONLY). |
| 110089005Q | 2021-05-03. Service bulletin. EQUIPMENT. This Warranty Administration bulletin provides information on Dealer Empowerment for Goodwill, Customer Enthusiasm and Policy (U.S. Only). |
| 1008110001I | 2021-05-03. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin provides information on proper use of floor mats. |
| 21NA043 | 2021-05-03. Service bulletin. EQUIPMENT. 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. |
| 20NA132 | 2021-05-03. Service bulletin. ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements. |
| 18NA099 | 2021-05-03. Service bulletin. EQUIPMENT. This bulletin provides information for use on a Product Assistance Claim (PAC), which is formerly known as a Product Allegation Resolution (PAR) claim. |
| 16NA109 | 2021-05-03. Service bulletin. STEERING. This service bulletin provides a procedure inspecting for excess grease or Sealant on the Exterior of the steering gear due to seeing grease or sealant on certain locations on the gear. |
| 150089004C | 2021-03-08. Service bulletin. SUSPENSION:FRONT:MACPHERSON STRUT; SUSPENSION:FRONT:SHOCK ABSORBER; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT. This service bulletin provides technicians with updated information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage. |
| 18NA073 | 2021-03-01. Service bulletin. ENGINE. This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement. |
| 040089015V | 2021-03-01. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This bulletin provides information on Warranty Administration ? Required Operating Procedures - 8 Points (U.S. Only). |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.