MagnaFlow Exhaust, Mufflers & Cat Converters - Quality

MagnaFlow 4 in. x 9 in. x 11 in. Oval Straight-Through Performance Exhaust Muffler 11378

MagnaFlow 4 in. x 9 in. x 11 in. Oval Straight-Through Performance Exhaust - Main image
$107.1 $170 In stock

Category: Performance Exhaust

The MagnaFlow 4 X 9in. Oval Straight-Through Performance Exhaust Muffler 11378 is engineered to enhance your ride with a healthy helping of our signature exhaust sound and dyno-proven performance thanks to its free-flowing straight-through perforated stainless steel core wrapped in stainless steel mesh and acoustic fiber fill. The reversible, universal 2.25/2.25in. diameter inlet/outlet Straight-Through layout allows you to install it in whatever orientation and configuration you see fit. However, professional installation is highly recommended. Muffler 11378s weight-optimized 4x9x11in. oval-shaped body features a satin finish that elevates the overall aesthetics of your current exhaust setup. 11378 is made of durable, corrosion resistant stainless steel and produced using cutting-edge CNC precision robotic manufacturing techniques, all backed by MagnaFlow's limited lifetime construction warranty.

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Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

Isabella V. ★★★★★

Installed this on my truck over the weekend and the dyno-proven performance is real—I can actually feel a difference in throttle response. The straight-through design gives it a deep, aggressive tone without being obnoxious on the highway.

Andrew ★★★★★

Swapped out my stock muffler for this oval straight-through design and the difference is night and day—noticeably deeper tone without being obnoxious on the highway. Fit was straightforward with the 4 inch inlet and the dyno-proven performance bump seems real enough.

Julian S. ★★★★★

The deep, throaty rumble at startup instantly told me I made the right choice, and the dyno-proven performance bump was noticeable during my morning commute.