Magnaflow · New

MagnaFlow Muffler Mag 3in 409SS 14X4X9 3 O/O

Name: MagnaFlow Muffler Mag 3in 409SS 14X4X9 3 O/O
Brand: Magnaflow
SKU: mag11239
Price: 149.00 USD

MPN 11239 · Store SKU mag11239

$149.00

CHECK AVAILABILITY0 in supplier warehouses. Ask JuiceBuilt about availability.

Supplier stock checked 11/7/2026, 9:59:42 AM UTC. Adding a part does not reserve it.

30-day returns for unopened, unused new parts

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

Shipping & returns ↗This policy does not limit rights required by law.

Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.

Product details

The MagnaFlow 4 x 9in. Oval Straight-Through Performance Exhaust Muffler 11239 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 3/3in. 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 11239s weight-optimized 4x9x14in. oval-shaped body features a satin finish that elevates the overall aesthetics of your current exhaust setup. 11239 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. Magnaflow Straight-Through Performance Muffler; 3in. Offset/Offset; 4x14x9 Body Straight-Through Performance Muffler; 3in. Offset/Offset; 4x14x9 Body Straight-Through Performance Muffler; 3in. Offset/Offset; 4x14x9 Body MagnaFlow 3 in/3 in Offset/Offset; 4 in x 14 in x 9 in Body Muffler 3 in/3 in Offset/Offset; 4 in x 14 in x 9 in Body Muffler

Manufacturer fitment & guides

Check 11239 against the manufacturer’s application information below.

MagnaFlow manufacturer exhaust application catalog ↗

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What is the return policy?

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

The customer pays return shipping for a change-of-mind return.

Any actual supplier restocking charge is disclosed before purchase.

Clearance and scratch-and-dent parts are final sale. No returns or refunds.

Read the full shipping & returns policy ↗

This policy does not limit rights required by law.

MagnaFlow Muffler Mag 3in 409SS 14X4X9 3 O/O

Product details

Manufacturer fitment & guides

THE NEXT PART
OF YOUR BUILD.

Free shipping on $100+ orders.

Build with the right brands.

Find your next upgrade.

Make the whole setup work.

A few things to know.

Your build.

Delivery & checkout

Delivery address