Flowmaster American Thunder Axle-Back, Dual 4.50in Black Ceramic Tips
Fits 2019-2024 (DT / new body) 5.7L HEMI V8 (DT) · 5.7L HEMI V8 eTorque (DT)
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Price tracked 9 times since Jul 26, 2026: low $449.95, high $449.95, currently $449.95.
Requires: MUST HAVE FACTORY DUAL TAILPIPES. Flowmaster states it does not fit trucks with a factory single tailpipe, and does not fit the Classic body at all.
where to buy · 2 retailers tracked
An axle-back replaces only the last section of exhaust, behind the rear axle: the tailpipes and tips. It is the shortest, cheapest way to change how the truck sounds without touching the muffler or anything under the middle of the truck.
why this one — This is the entry point for exhaust on this truck at under 500 dollars, roughly a third of what the cat-back systems here cost, and it is the only axle-back in the lane. You get 2.50in tailpipes in place of the factory 2.25in and dual 4.50in black ceramic-coated tips, and Flowmaster rates the sound Moderate, so it is a step up from stock rather than a truck that announces itself. Check your tailpipes first: Flowmaster is explicit that it will not fit a truck with a single factory tailpipe, and it will not fit a Classic.
Flowmastermufflers.com product page for 817850 gives tubing and tip sizes and a Moderate sound rating but publishes no hp or tq figure. Not invented.
No published gain figure for this part, and nothing here is a guarantee. Price is a list price and can lag the retailer; confirm at checkout. See our affiliate disclosure.