2015.5 - 2016 GM 6.6L LML Duramax T87 | Allison Transmission Tuning by PPEI

Great upgrade

About 600 miles in and drives much better. Definitely a major upgrade to wake up the truck and quality of life for driving it. Thanks again to Logan for the help.

Duramax Transmission Tune

This transmission tune made the best difference for our 2016 Duramax. The truck was deleted and the engine was tuned years ago and it had also gotten a bigger turbo but the truck just felt slow and the pedal response wasn’t there. After installing the PPEI transmission tune, the truck feels like it finally woke up. It gets up and goes now and shifts awesome. I’m very happy with PPEI, they definitely know what they’re doing!

2015 GMC sierra Transmission Tune!

The best tunes you can get hands down! Seemed to wake the truck up with perfect lock up and smooth shifts! Cant wait for delete tunes to hopefully come back. Will definitely be keeping an eye out for them!