[Mr. Stacy]

This does not say "will void your entire warranty".

Originally Posted by GM 2015 Warranty

Aftermarket Engine Performance Enhancement Products and Modifications

Some aftermarket engine performance products and modifications promise a way to increase the horsepower and torque levels of your vehicle’s powertrain. You should be aware that these products may have detrimental effects on the performance and life of the engine, exhaust emission system, transmission, and drivetrain.

The Duramax Diesel Engine, Allison Automatic Transmission®, and drivetrain have been designed and built to offer industry leading durability and performance in the most demanding applications. Engine power enhancement products may enable the engine to operate at horsepower and torque levels that could damage, create failure, or reduce the life of the engine, engine emission system, transmission, and drivetrain.

Damage, failure, or reduced life of the engine, transmission, emission system, drivetrain or other vehicle components caused by aftermarket engine performance enhancement products or modifications may not be covered under your vehicle warranty.

Originally Posted by 2015 GM Warranty

Original Equipment Alterations

This warranty does not cover any damage or failure resulting from modification or alteration to the vehicle's original equipment as manufactured or assembled by General Motors. Examples of the types of alterations that would not be covered include cutting, welding, or disconnecting of the vehicle's original equipment parts and components.

Additionally, General Motors does not warranty non-GM parts, calibrations, and/or software modifications. The use of parts, control module calibrations, software modifications, and/or any other alterations not issued through General Motors will void the warranty coverage for those components that are damaged or otherwise affected by the installation of the non-GM part, control module calibration, software modification, and/or other alteration.

The only exception is that non-GM parts labeled “Certified to EPA Standards” are covered by the Federal Emissions Performance Warranty.