FITMENT

• 2017-2023 6.6L Silverado & Sierra Duramax 2500HD/3500HD trucks.
• Fit Crew Cab, Double Cab, Regular Cab with Standard/Long Bed.
• Does NOT Fit: 3500/4500/5500 Cab & Chassis commercial models.

DESCRIPTION

Product Overview

• The 2017–2023 Duramax L5P is heavily choked by two factory bottlenecks: the restrictive under-cab DPF/CAT filter blocks and the rough, narrow 3.5" downpipe directly behind the turbo. Over time, these components plug with ash, triggering frequent, fuel-guzzling regeneration cycles that drop mileage to a poor 12–14 MPG.
• Additionally, the fragile L5P emissions network is highly prone to DEF heater, pump, and NOx sensor failures that instantly trigger a 55 MPH Limp Mode countdown. Forcing exhaust through these combined restrictions traps intense backpressure, spiking towing EGTs past 1,300°F and shortening turbo life.

Key Features

• Industrial-Grade T-409 Stainless Steel: Crafted from heavy-duty mandrel-bent T-409 SS to withstand intense thermal expansion and contraction cycles without cracking, warping, or scaling.
• Continuous 4" Mandrel-Bent Tubing: Engineered with smooth, uniform 4-inch diameter paths featuring zero internal neck-downs or restrictive bungs, providing the ultimate sweet spot for exhaust gas velocity.
• Maximum EGT Heat Management: The most effective modification for dropping exhaust backpressure to near zero, significantly cooling engine and transmission operating temperatures under heavy sustained towing loads.
• True Downpipe-Back Overhaul: Replaces the heavy under-cab DPF, DOC, SCR, and stock muffler sections all the way to the rear tail tip in one clean sweep. Safely throws out your rusted original rear factory sections.

FAQ

Q: Does this pipe include a new turbo downpipe?

A: No. This system connects directly to your factory downpipe's rear outlet via a 4-bolt flange. However, the restrictive stock 3.5" downpipe has rough castings that choke airflow right at the turbo. To fix this secondary bottleneck, we recommend upgrading to our smooth L5P Downpipe to slash EGTs and maximize exhaust velocity.

Q: Which CAN bus plugs do I need to buy?

A: You must choose strictly based on your truck's specific model year, as GM changed the wiring pins and communication protocols mid-generation. They are not interchangeable: For 17–19 L5P Models: You need the 2017-2019 CAN Bus Plug. For 20–23 L5P Models: You need the 2020-2023 CAN Bus Plug.

Q: Is it worth the extra $364 over the mid-section delete pipe?

A: If your factory rear tailpipe is in perfect condition and you want to keep truck quiet on a budget, Race pipe works great. However, if your original tailpipe or hangers are heavily rusted and ready to snap after years on the road, or if you want a true, aggressive straight-pipe exhaust note, this full system is the complete solution.

Q: How loud is this system? Will it cause cabin drone?

A: On 20–23 trucks, a full delete will void the factory powertrain and emissions warranty. For 17–19 models, the original 5-year/100k-mile factory coverage has already expired. Note that aftermarket extended warranties typically exclude any emission-modified vehicles.