2020-2026 GM 2500HD/3500HD 6.6L L5P Duramax Modules

After upgrading and modifying your 2020-2026 GM 6.6L Duramax L5P, your transmission may struggle with shifting smoothly and reliably due to the increased power demands. A premium transmission control module is great for allowing your transmission to calculate the right time to shift, and preventing rough or unreliable gear changes. These transmission modules communicate directly with your truck’s computer, sending proper OBD II codes to ensure consistent and optimized shifting for every situation. In addition to improving gear shifting, these modules can detect transmission malfunctions, alerting you to potential issues before they lead to serious damage or expensive repairs. Be sure to check out some other Tuners & Monitors to optimize your GM 2500HD/3500HD's efficiency even further. GM Duramax Fitments: 2020, 2021, 2022, 2023, 2024, 2025, 2026 GM 6.6L Duramax. Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali. Some exceptions apply, please see individual product pages for specific fitments.