Description
Overview
The Flowmaster American Thunder Crossmember-Back Exhaust System is a complete bolt-on upgrade engineered specifically for 1967-1972 Ford F-100/F-250/F-350 two-wheel drive long bed V8 trucks equipped with a side-mounted auxiliary fuel tank. Designed to start after a set of factory manifolds or headers, this crossmember-back system replaces the tired, restrictive stock plumbing with a purpose-built exhaust that improves flow while delivering the unmistakable Flowmaster sound classic truck owners crave.
At the heart of the system are Flowmaster’s Super 44 Series performance mufflers. These finished-in-black mufflers measure 19.50 inches overall with a center 2.50-inch inlet and an offset 2.50-inch outlet, giving any V8 a deep rumble with that signature Flowmaster tone. Paired with all mandrel-bent 2.50-inch 409 stainless steel tubing and a built-in H-pipe crossover, the design maximizes the flow of exhaust pulses for better performance while adding the long-term durability of stainless steel construction.
Key Benefits
This is a system built for owners who want an aggressive-to-moderate sound level both inside and outside the cab. The mandrel-bent silver tubing preserves diameter through every bend, and the H-pipe crossover helps balance the dual exhaust for a fuller, more refined tone. Because it is a true crossmember-back kit, everything downstream of your manifolds or headers is covered.
- Complete crossmember-back kit with all mandrel-bent 2.50-inch 409 stainless steel tubing
- Built-in H-pipe crossover for balanced flow and improved performance
- Super 44 Series dual mufflers (19.50-inch length, center inlet, offset outlet) for a deep, aggressive rumble
- New hangers and all mounting hardware included for an at-home installation
- Silver pipe finish with black mufflers for a clean, purposeful look
- CARB (California) compliant, Emission Code 5
Choose Your Tailpipe Exit
Configure the exhaust to match your build. Three dual tailpipe exit styles are available: straight out the rear, side exit behind each rear tire, or dumped behind the rear tires. Select the routing that best fits your truck’s stance and your preferred sound character. Please note the kit is supplied as muffler kit only, and exhaust tips are sold separately, giving you the freedom to finish the system your way.
Fitment
This American Thunder system fits 1967-1972 Ford F-100/F-250/F-350 2-wheel drive long bed V8 trucks with a side-mounted auxiliary fuel tank. Long bed trucks only. It installs after factory manifolds or headers and comes complete with the dual tailpipes and new hangers needed to get the job done. This exhaust system is covered by Flowmaster’s Lifetime Limited Warranty. California Proposition 65 warning applies.
