Description
Overview
The Flowmaster Flow FX Extreme Cat-Back Exhaust System is engineered for the 2014-2019 Chevrolet/GMC Silverado/Sierra 1500 equipped with the 4.3 or 5.3-liter engine. Built around a Flow FX series muffler, this stainless steel cat-back system delivers an aggressive-to-moderate exhaust note and a real boost in performance, making it a smart upgrade for truck owners who want more sound, more flow, and better trail-ready clearance.
At the heart of the system is 3.0-inch mandrel-bent 409 stainless steel tubing. The mandrel bending keeps the inner diameter consistent through every curve, maximizing exhaust flow, while the 409 stainless construction stands up to heat, corrosion, and years of hard use. On the dyno, this setup produced max gains of 11 horsepower and 15 lb-ft of torque at the rear wheels.
Extreme Turndown Design
What sets the Flow FX Extreme apart is its turndown-style, dump exit positioned right after the muffler. By eliminating the over-axle tailpipe entirely, the system improves ground clearance and departure angle — a meaningful advantage when you’re pushing your Silverado or Sierra into more extreme off-road situations. Fewer pipes underneath also mean less to snag on rocks, ruts, and obstacles.
Key Benefits
- 3.0-inch mandrel-bent 409 stainless steel tubing for maximum flow and long-term durability
- Flow FX series muffler tuned for an aggressive-to-moderate sound level
- Turndown dump exit eliminates the over-axle tailpipe for improved ground clearance and departure angle
- Dyno-proven max gains of 11 hp and 15 lb-ft at the rear wheels
- Silver-finish muffler with a 37.70-inch overall length, center inlet, and 3.00-inch center outlet
- Single tailpipe configuration with all necessary hardware included
Easy, Bolt-On Installation
The Flow FX Extreme is designed to make installation straightforward. It mounts using factory hanger locations, so there’s no need to modify your truck’s underbody or fabricate custom mounts. All of the necessary hardware is included in the kit, letting you complete the swap with basic hand tools and get back on the road — or the trail — quickly.
Fitment
This cat-back system is built specifically for the 2014-2019 Chevrolet/GMC Silverado 1500 and Sierra 1500 with the 4.3 or 5.3-liter engine. It is CARB (California) compliant with Emission Code 5, so it’s a legal upgrade in all 50 states. Please note the California Proposition 65 warning applies.
Backed by Flowmaster’s Lifetime Limited Warranty, the Flow FX Extreme combines aggressive tone, proven power gains, and off-road-friendly clearance in one durable stainless steel package. Upgrade your half-ton with a system that looks, sounds, and performs the part.
