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 your truck to verify your turbo discharge style before purchasing!
DESCRIPTION
Product Overview
- Late-production 2015.5-2016 LML trucks have hit their peak emissions failure window. Soot-choked DPFs, blown DEF heaters, and failed sensors frequently trigger Limp Mode while tanking fuel economy to 13-14 MPG.
- Furthermore, towing with these restrictions traps intense backpressure, spiking EGTs past 1,300°F and straining the turbo. At this age, mid-section patch pipes aren't enough, as the stock 10-year-old tailpipes and hangers are often heavily rusted and ready to snap.
Key Features
- Rugged T-409 Stainless Steel Build: Manufactured from industrial-grade T-409 SS, perfectly optimized to expand and contract under intense thermal cycling without cracking or warping.
- Continuous 4" Mandrel-Bent Tubing: Engineered with smooth, 4" diameter paths featuring zero internal neck-downs or restrictive bungs, providing the ultimate sweet spot for exhaust gas velocity.
- Substantial EGT & Heat Reduction: Instantly drops exhaust backpressure, allowing scorching gases to exit the motor rapidly, dropping EGTs significantly under heavy sustained towing loads.
- Precision 3-Bolt Flange Receiver: Equipped with a heavy-duty, CNC machine-cut 3-bolt flange welded at the inlet, guaranteeing a direct, leak-free bolt-on connection to your 15.5-16 factory downpipe output.
FAQ
Q: How loud is this full straight-pipe system? Will it drone inside the cab?
A: This Full straight pipe delivers a crisp tone and turbo whistle but causes highway cabin drone. For daily commuting or family towing, we highly recommend adding 4" Muffler. It tames harsh drone and raspy frequencies perfectly while preserving a deep, muscular diesel V8 rumble.
Q: Will this stop my truck's DEF system from throwing codes and failing?
A: Yes. Once you flash a delete tune and install this pipe, the entire DEF/SCR system is deactivated in the software. The DEF fluid injector stops spraying, the failure-prone tank heater stops cycling, and the NOx sensors are turned off. You will say goodbye to DEF-related check engine lights and countdown timers forever.
Q: How much horsepower will the 5" system add over this 4" version?
A: Zero, unless heavily modified. On a stock turbo, both systems make identical horsepower, but the 4" version preserves sharper low-end throttle response. Choose the 5" pipe only if your LML features a built transmission and aftermarket turbo to handle maximum high-RPM airflow.
Q: Can I install this 4" downpipe-back system myself in my garage?
A: Yes. The system is a direct bolt-on replacement that slips perfectly into your truck's factory rubber mounts. It takes about 1 to 2 hours in a driveway using basic hand tools and jack stands. We highly recommend soaking the old factory bolts in penetrating oil a few hours before starting.
