FITMENT
- 2015.5-2016 6.6L Silverado & Sierra Duramax 2500HD/3500HD LML engine models with the 3-bolt flange.
- Does NOT Fit 2011-2015.5 model with the V-Band Clamp style.
- Please physically inspect underneath truck to verify your turbo discharge style before purchasing!
DESCRIPTION
Product Overview
- In mid-2015.5, GM updated the 6.6L Duramax LML downpipe connection to a 3-hole triangular flange. Installing an earlier LML pipe on a 2015.5–2016 model results in severe fitment issues and exhaust leaks. Additionally, running a completely open straight pipe on these late LML trucks can cause intense cabin drone during highway towing.
- The 4" LML DPF Delete Pipe is engineered specifically for late-model LML trucks. The integrated high-flow straight-through performance muffler flushes out intense backpressure and lowers towing EGTs while keeping the exhaust tone deep, refined, and completely drone-free inside the cab.
Key Features
- Premium Material: Full 4-inch mandrel-bent T409 stainless steel tubing built to resist extreme thermal stress, road salt, and harsh winter corrosion.
- Sharply Lower Towing EGTs: Relieves severe turbine backpressure right behind the downpipe, allowing exhaust temperatures to drop rapidly under heavy payloads and long hill climbs.
- Permanently Stop DEF Errors: Eliminates failure-prone DEF heaters, pumps, and NOx sensors that trigger automatic 55-MPH dealer Limp Mode lockouts.
- Quiet High-Flow Performance: Deletes the choked factory DPF, CAT, and SCR while incorporating a straight-through performance muffler to eliminate harsh highway cabin drone.
FAQ
Q: What is the main benefit of choosing the "With Muffler" version?
A: Both versions maximize flow and lower EGTs equally. However, this kit adds a straight-through performance muffler to eliminate harsh exhaust rasps and highway cabin drone for a quieter ride.
Q: Does the included performance muffler restrict exhaust airflow?
A: No. It features a full 4-inch straight-through internal core that lets exhaust gases pass freely without adding backpressure or trapping heat.
Q: Where can I look under my truck to visually confirm I have a 3-hole flange?
A: Crawl under the passenger side of your truck behind the front tire/axle area where the front downpipe connects to the mid-pipe. If you see three triangularly spaced bolts securing the exhaust connection, your truck is a 2015.5+ model and requires this exact kit.
Q: Is it necessary to remove the DEF tank under the truck after installing this pipe?
A: It is optional. Once your ECM is flashed with a custom delete tune, the DEF pump and heater are electronically disabled. You can leave the empty DEF tank mounted in place, or remove it entirely to clean up the undercarriage and gain extra ground clearance.
