Ignitions and Electrical› Computers, Chips, Modules and Programmers

Spelab

TCM Tuning Kit

$1,047.98

SKU: SPCI08599-ES08074-ES08067

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Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
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Professional / shop required

Overview

The Spelab TCM Tuning Kit is a transmission calibration package designed for 2017-2026 GMC and Chevy 6.6L Duramax L5P trucks. This kit recalibrates shift timing, shift points, torque converter lockup, and transmission hydraulic line pressure. It requires no physical component replacement, only licensing and flashing tune files to your factory TCM.
Show original supplier description
The Spelab L5P Transmission (TCM) Tuning Kit provides premium transmission calibrations for 2017–2026 GM Duramax L5P trucks, specifically optimized to complement upgraded powertrains. This package recalibrates critical transmission functions including shift timing, shift points, torque converter lockup behavior, and transmission hydraulic line pressure. The system is designed to work with your existing factory T87A (2017–2019) or T93 (2020–2026) TCM units, requiring no additional hardware. Key features include redesigned shift maps tailored for heavy diesel hauling and daily driving, custom shift point calibration that raises or lowers trigger points beyond OEM limits, and precisely calibrated shift timing for smooth, consistent gear changes. The kit also offers optimized torque converter lockup logic to reduce slippage under load and improve fuel efficiency, along with recalibrated transmission line pressure for firmer clutch clamping to reliably handle increased torque output. This tuning package is intended for off-road use only and is a final sale, non-refundable product. Compatibility is limited to 2017-2026 Chevrolet Silverado 2500/3500 and GMC Sierra 2500/3500 models equipped with the 6.6L L5P Duramax diesel engine. A specific OBD2 Flash Tuning Interface is required for installation, and the system is only compatible with MPVI3 or MPVI4 tuners. The tuning process involves licensing your factory TCM and uploading pre-built tune files.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandSpelab
Part NumberSPCI08599-ES08074-ES08067
CategoryIgnitions and Electrical
5,000+ Trusted brands
1M+ Enthusiasts
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(760) 282-4645 hello@motormia.co

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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