Flowmaster Signature Series Cat-Back Exhaust for F-150 (2021-2025) Black - 738115

Flowmaster Signature Cat-Back For F-150 (Single-Side Exit) 

Built to howl. Tuned to win. Flowmaster’s Signature Series is their premium, made-in-USA system: full 304 stainless, hand TIG-welded, and finished with a 4.5" black-chrome tip. It delivers that clean, modern look with the aggressive-to-moderate tone F-150 owners want—plus real, dyno-proven gains over stock.

Why it hits

• Premium 304 SS: Maximum corrosion resistance and a high-end brushed finish (no cheap aluminized shortcuts).

• Hand TIG-welded: Tighter heat control and cleaner, stronger seams than MIG.

• Black-chrome tip (4.5"): Upscale, motorsport vibe without screaming for attention.

• Signature Series muffler: Deeper, performance tone with more flow than OEM.

• Real performance: Dyno-proven power and torque gains you can feel.

• Made in the USA with a Limited Lifetime Warranty on stainless components.

What it fits

• Ford F-150 — select late-model applications.
  Choose your year/engine/wheelbase on the product page to match the correct part number.

Sound

• Idle/Cruise: Refined burble, moderate presence.

• Throttle/WOT: Confidently aggressive—classic Flowmaster authority.
  (Drone characteristics vary by cab/bed/gear—Flowmaster tunes this to stay daily-drivable.)

Install notes

• Type: Cat-Back, single-side exit (passenger side, behind tire)

• Time: ~2 hours for most driveway installs

• Tools/Method: Basic hand tools; welding may be required per application—professional install recommended if you don’t weld.

• Packaging: Keep/repurpose all foam and boxes for any future return or warranty shipping.

Tech specs

• Exhaust layout: Single 3.0" mandrel-bent 304 stainless

• Muffler: Flowmaster Signature Series, single-in/single-out (1)

• Tip: 4.5" round, angle-cut, black-chrome stainless steel

• Includes: Muffler, tailpipes, tip, clamps/hardware, instructions

• Required welding: Yes (per manufacturer/application)

• Estimated install time: 2 hours

• Tone: Aggressive/Moderate

• Warranty: Limited Lifetime (manufacturer)

Builder’s checklist

• Verify year/engine/drive/bed & wheelbase before ordering.

• Test-fit everything before tightening clamps or welding.

• Photograph your unbox/install—helps with support and warranty.

• Pair with a high-flow intake/tune for maximum results.

Questions on fitment before you buy? Ping us and we’ll sanity-check your build!