L5P TCM Tuning Kit

The Spelab L5P TCM Tuning Kit provides premium transmission calibrations for 2017–2026 GM Duramax L5P trucks, optimized for upgraded powertrains. This kit allows you to license your factory TCM and upload pre-built tune files to entirely recalibrate shift timing, shift points, torque converter lockup behavior, and transmission hydraulic line pressure. No physical component replacement is necessary. Key features include redesigned shift maps for heavy hauling and daily driving, custom shift point calibration beyond OEM limits, and precisely calibrated shift timing for smooth, consistent gear changes. The torque converter lockup logic is revised to cut slippage under load and boost fuel efficiency, while transmission line pressure is recalibrated for firmer clutch clamping to reliably handle increased torque. This tuning package is compatible with your stock T87A (2017–2019, 6 & 10-Speed) and T93 (2020–2026, Diesel only) TCM units. It requires an OBD 2 Flash Tuning Interface and includes 4 OBD2 Tuning Credits and Vehicle Licensing. Please note that this product is intended for off-road use only and is a final sale, non-refundable item. **Fitment:** * 2017-2026 Chevrolet Silverado 2500/3500 L5P 6.6L Duramax * 2017-2026 GMC Sierra 2500/3500 6.6L L5P 6.6L Duramax **Important Notes:** * Requires an MPVI3 or MPVI4 tuner. * This bundle is exclusively for L5P diesel applications; it does not fit gas engine trucks. * A Windows-based laptop is required for the tuning software; Apple products will not work. * This product is intended for off-road use only and is a final sale, non-refundable item.