GDP EZ Lynk Transmission Tune File T87A (2017-2019 6.6L L5P Duramax)

If you’re running a tuned L5P but still stuck with stock TCM mapping, you're leaving serious performance on the table. The GDP EZ Lynk T87A Transmission Tune File is the missing piece. It’s built to unlock the full potential of your transmission by improving shift timing, torque management, and drivability—no more sluggish shifts or gear hunting.

This is not your average trans tune. It’s built specifically for the 2017–2019 L5P Duramax equipped with the T87A module, designed to work with your engine tuning to deliver smoother shifts, more power to the ground, and a way better driving experience whether you're loaded up or cruising empty.

We offer:

Trans Tune File – Custom-calibrated for your exact setup and driving needs. Improves shift firmness, reduces flare, and optimizes converter lockup for better towing and throttle feel.

Pair this file with your GDP engine tuning and you’ve got a combo that rips—and still plays nice with long-term reliability.

Why Choose GDP TCM Tunes?
✔ Matched to your GDP engine tuning for seamless performance
✔ Faster, crisper shifts under load and at WOT
✔ Reduced gear hunting and improved towing manners
✔ Unlocks true torque potential of your L5P

Don’t let factory TCM tuning hold your truck back. Upgrade with GDP and feel the difference every time you hit the throttle.