FITMENT
- 2017-2023 6.6L GMC Chevy Duramax L5P 2500HD & 3500HD Diesel.
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Compatible with all cab styles including Regular Cab, Double Cab, and Crew Cab.Excluding Cab & Chassis configurations.
DESCRIPTION
Product Overview
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Protect your drivetrain and hold the power. This premium package is a 100% Digital Custom Calibration designed exclusively to unlock and tune the encrypted factory Transmission Control Module (TCM) on 2017-2023 GMC Sierra and Chevy Silverado 2500HD/3500HD 6.6L L5P Duramax trucks.
- The factory Allison 6-speed and 10-speed transmissions are heavily restricted by lazy OEM shift mapping and low line pressures.
- Once you increase your engine's performance, the factory TCM cannot supply enough clamping force, leading to clutch slippage and premature drivetrain failure.
Key Features
- Increased Line Pressure: Electronically bumps internal hydraulic oil pressure to lock your clutch packs tight under heavy loads, stopping transmission slippage dead in its tracks.
- Optimized Shift Points: Eliminates sloppy factory shift delays and awkward gear hunting, delivering crisp, perfectly timed shifts whether empty or maxed out on a heavy tow.
- Improved Converter Lockup: Re-calibrates the torque converter clutch (TCC) to lock up earlier and smoother, transferring raw power directly to the ground and lowering running temperatures.
- 100% Digital Delivery: Seamlessly generated by our elite calibration engineers and sent straight to your email or cloud profile within 24 business hours.
FAQ
Q: Why does my 2017-2023 L5P need a dedicated TCM tune?
A: GM heavily encrypted the T50 and T93 Allison computers. If you tune or delete your L5P engine without upgrading the TCM, the stock transmission will quickly slip and burn its clutches under the new low-end torque. This tune ensures your transmission safely manages the added power.
Q: What is the relationship between HP Tuners and the L5P TCM Unlock?
A: They work hand-in-hand and are both required. First, the TCM Unlock breaks through GM's encrypted firewall on the Allison computer (T50/T93). Once unlocked, you use the HP Tuners device to physically flash and write our custom shift-mapping and line pressure files into the transmission.
Q: Will this fix the harsh shifting or gear hunting while towing?
A: Yes, absolutely. The factory Allison programming prioritizes emissions over driveability, causing it to lug the engine or shift lazily. Our file optimizes the shift schedules so your truck stays in the sweet spot of its powerband, drastically reducing gear hunting on steep highway.
Q: What is the installation process for this TCM tune?
A: Place your order and submit your 17 VIN along with your truck setup.
Use your Windows laptop and HP Tuners device to read your stock transmission file.
Email us the file; our engineers will custom-calibrate it and email your new TCM file back within 24 hours.
Flash it back into your truck via the OBD-II port. The entire flash process takes less than 15 minutes.
