Chevrolet 6500 2018–2025 — technical service bulletin

Bulletin 20-NA-203 · NHTSA communication 11005341 · issued Jul 17, 2024

Technical service bulletin

communication type

Engine

component

2018–2025

model years

vehicle entries

Official summary

This informational bulletin explains how the regen works for the DEF system and how it works at different levels.

Vehicles covered

2019 Chevrolet 6500
2019 Chevrolet Duplicate Silverado 5500
2018 Chevrolet Silverado 1500
2018 Chevrolet Silverado 2500
2019 Chevrolet Silverado 2500
2020 Chevrolet Silverado 2500
2021 Chevrolet Silverado 2500
2022 Chevrolet Silverado 2500
2023 Chevrolet Silverado 2500
2024 Chevrolet Silverado 2500
2018 Chevrolet Silverado 3500
2019 Chevrolet Silverado 3500
2020 Chevrolet Silverado 3500
2021 Chevrolet Silverado 3500
2022 Chevrolet Silverado 3500
2023 Chevrolet Silverado 3500
2024 Chevrolet Silverado 3500
2019 Chevrolet Silverado 4500
2020 Chevrolet Silverado 4500
2021 Chevrolet Silverado 4500
2022 Chevrolet Silverado 4500
2023 Chevrolet Silverado 4500
2024 Chevrolet Silverado 4500
2019 Chevrolet Silverado 5500
2020 Chevrolet Silverado 5500
2021 Chevrolet Silverado 5500
2023 Chevrolet Silverado 5500
2024 Chevrolet Silverado 5500
2019 Chevrolet Silverado 6500
2021 Chevrolet Silverado 6500
2022 Chevrolet Silverado 6500
2023 Chevrolet Silverado 6500
2025 Chevrolet Silverado 6500
2018 Chevrolet Silverado LT
2018 GMC Sierra 1500
2018 GMC Sierra 2500
2019 GMC Sierra 2500
2020 GMC Sierra 2500
2021 GMC Sierra 2500
2022 GMC Sierra 2500
2023 GMC Sierra 2500
2024 GMC Sierra 2500
2018 GMC Sierra 3500
2019 GMC Sierra 3500
2020 GMC Sierra 3500
2021 GMC Sierra 3500
2022 GMC Sierra 3500
2023 GMC Sierra 3500
2024 GMC Sierra 3500
2018 GMC Sierra Denali

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.