2015.5-2016 LML 6.6L Duramax 5" Downpipe-Back Exhaust for Chevy GMC 2500HD 3500HD

What Is an LML Downpipe-Back 5" Exhaust System?

This is a 5" Downpipe-Back exhaust system specifically designed for 2015.5–2016 Chevrolet Silverado and GMC Sierra 2500HD/3500HD trucks equipped with the 6.6L Duramax LML diesel engine.

5 Core Upgrade Benefits

🌡️ Significantly Lower Exhaust Gas Temperatures (EGT)

• The oversized piping greatly reduces exhaust restriction and allows gases to exit more quickly. During heavy towing or long-distance highway driving, this can effectively lower engine and turbo temperatures and help extend the life of critical components.

⚡ Unleash Maximum Horsepower & Torque

• Eliminate restrictive backpressure, allowing the turbo to spool faster, significantly reducing turbo lag, sharpening throttle response, and delivering stronger, more consistent towing power.

⛽ Improve Fuel Economy

• With smoother exhaust flow, the engine can “breathe” more efficiently, significantly improving combustion efficiency and delivering better fuel economy during steady-speed cruising and towing.

🔊 Powerful Diesel V8 Exhaust Sound

• The 5" large-diameter piping combined with a straight-through design replaces the dull factory exhaust note with a deeper, fuller, and more powerful diesel V8 sound.

🛡️ Premium T409 Stainless Steel for Superior Corrosion Resistance

• Built from high-quality T409 stainless steel to withstand exhaust heat, mud, debris, and road salt, delivering far greater durability than ordinary factory piping.

How to Tell a 2015 from a 2015.5 Model

Before ordering, visually inspect your truck's exhaust connection.

Tuning Is Required

Because this exhaust setup changes the factory emissions configuration, compatible tuning is required for applicable off-road or competition-use builds. Make sure the tuner and calibration you choose support your 2015.5–2016 6.6L LML Duramax.

For a simpler standalone solution, consider the Mini Maxx V2. If you prefer a cloud-based platform with remote tuning support, the EZ LYNK Auto Agent 3 is another option and requires a compatible tune file.