---tab Description--- Description Want to keep your DPF but still get that deep, aggressive exhaust sound for your 2011-2016 6.7L Powerstroke? Upgrade to SPELAB's DPF-back pipe! This product is designed for users who want to keep their factory DPF and upgrade the exhaust piping behind it. You can choose between affordable 409 stainless steel (a direct OE replacement that solves rust and aging issues) or premium 304 stainless steel for better durability. Enjoy the black-coated exhaust tip for a sleek look and the expanded outlet diameter for improved sound and flow. Get the rumble you want—without deleting your DPF! Parameter T304 T409 Corrosion Resistance 18% Cr, 8% Ni(Better) 11% Cr, trace Ti(Good) High Temp Resistance ≤870°C ≤800°C Oxidation Resistance Excellent Good Salt/Cl⁻ Resistance Excellent Good Sulfide Resistance Excellent Good Estimated Lifespan 10-15+ years 7-12 years Specification Filter Back Mateial T409/T304 Stainless Steel Exhaust tip Mateial T201 Stainless Steel Exhaust Diameter 4" Installation Bolt-on (no welding required) Sound Level Performance-enhanced tone (deeper but not overly loud) Key Features Performance Boost – Reduces exhaust restriction for better horsepower, torque, and fuel efficiency. Durable Construction – T409 stainless steel resists corrosion and withstands daily use. Compared to T409, T304 contains higher nickel content (8-10%) for enhanced rust protection, especially in coastal or high-salt conditions. Easy Bolt-On Installation – Uses factory-style hangers for a perfect fit (no welding needed). Enhanced Exhaust Sound – Deeper, more aggressive tone without excessive drone. OEM+ Fitment – Precision-engineered to match factory mounting points. DPF-Compatible – Works with your stock diesel particulate filter (emissions compliant). Stylish Black Exhaust Tip – Adds a rugged, custom appearance to your truck. What's in the BOX? 4"Extension Pipe x 1 Over-Axle Pipe x 1 Tail Pipe x 1 Hanger x 1 Exhaust Tip x 1 4" Wide band clamps x 2 Gasket x 1 7/16" Hex bolts x 3 7/16" Hex nutsx 3 Installation 4'' DPF Back Instruction for 6.7L Powerstroke 2011-2016 ---tab Fitment--- 2011-2016 Ford F-250 / F-350 / F-450 Super Duty 6.7L Powerstroke Does NOT fit Cab & Chassis configurations Note: For maximum performance, pair with a DPF/CAT delete pipe (off-road use only). ---tab FAQ--- Q1: Does this DPF Back exhaust system keep the factory DPF (Diesel Particulate Filter)?A1: Yes, this is a "DPF Back" system, meaning it only replaces the exhaust section after the DPF (including muffler/pipe). It does not delete the DPF, ensuring your truck remains emissions-compliant. Q2: Will this exhaust improve performance or fuel economy?A2: Since the DPF remains in place, gains are modest. However, the 4'' straight-through design reduces backpressure, which may slightly improve throttle response, torque, and exhaust flow efficiency. Q3: Does installation require cutting the stock exhaust? Do I need professional help?A3: Most DPF Back kits are bolt-on...