The MagnaFlow 5 X 8in. Oval Straight-Through Performance Exhaust Muffler 12256 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 2.5/2.5in. 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 12256s weight-optimized 5x8x18in. oval-shaped body features a satin finish that elevates the overall aesthetics of your current exhaust setup. 12256 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.
SPECIFICATIONS |
Series |
Straight-Through |
Muffler Type |
Straight-Through |
Material |
Stainless Steel |
Body Finish |
Satin |
Body Length |
18″ |
Body Shape |
5″ x 8″ Oval |
Body Width |
8″ |
Configuration |
Offset/Center |
Hanger Included |
No |
In/Out Diameter |
2.5″/2.5″ |
Inlet Diameter |
2.5″ |
Inlet Type |
Offset |
Outlet Diameter |
2.5″ |
Outlet Quantity |
1 |
Outlet Type |
Center |
Overall Length |
24″ |
Features

Signature MagnaFlow Sound
The 5″ x 8″ Oval body of muffler 12256 is engineered to deliver the deep, resonating sound that MagnaFlow mufflers are famous for.

Dyno-Proven Performance
Extensive dyno testing is used to ensure that this 5″ x 8″ Oval muffler increases engine power and performance by improving the flow dynamics and evacuation of exhaust gases.

Optimal Architecture & Construction
The internal architecture of this muffler features a straight-through perforated core with two-stage acoustic packing which maintains the velocity of exhaust flow while generating a smooth, deep exhaust tone. Proudly made in the USA.

Universal Fitment
12256’s universal design enables custom muffler placement and orientation to meet the particular spacing and mechanical requirements of your vehicle. Professional installation is highly recommended.