Overview
The MagnaFlow 12158 is a satin stainless steel muffler with a centered inlet, a dual offset outlet and 2.5-inch tubes. Its 100% stainless steel body is lap-joint welded for a rugged, solid build.
A straight-through perforated core sits inside stainless mesh wrap and acoustical fiber fill, which gives a smooth, deep tone. The muffler is universal fit, so it is not tied to a particular vehicle. Match the tube size and port layout to your exhaust before fitting.
Key features
- Lap-joint welded, 100% stainless steel construction
- Straight-through perforated core for a free flow path
- Stainless mesh wrap around the core
- Dense acoustical fiber fill for a deep, smooth note
- MagnaFlow Lifetime Warranty
Tailpipe fit and sound
Tube diameter sets how easily exhaust gas moves through the system. A muffler with the right diameter keeps flow steady, while a mismatch can raise back pressure or create a restriction that changes how the engine responds. When you compare sizes, measure the pipe itself rather than judging by an old clamp.
Port layout is the second check. A centered inlet with dual offset outlets can make the rear of the body sit at an angle, so the tailpipe may need a small change in bend or hanger position. Test-fit with the clamps loose and confirm the outlet points where you need it before final tightening.
Once installed, listen for rattles and check for soot at joints after the first few drives. Replace worn hangers before the body sags, since a sagging muffler can strain the welds and crack the shell over time.
- Measure both pipe diameters
- Test-fit with clamps loose
- Check hangers for stretch or cracking
Specifications
| Brand | MagnaFlow Exhaust |
|---|---|
| Part number | 12158 |
| UPC | 841380000743 |
| Finish | Satin |
| Material | 100% stainless steel |
| Muffler type | Straight through |
| Inlet location | Centered |
| Outlet location | Dual offset |
| Tube size (inlet/outlet) | 2.5 inches / 2.5 inches |
| Fitment listing | Universal fit |
| Warranty | Lifetime |
Vehicle fitment
No year, make, model or trim is attached to this muffler. Use the 2.5-inch tubes and centered inlet to judge whether it suits your pipe, and confirm fit for your vehicle before ordering.
This muffler has no vehicle attached. Confirm your vehicle’s year, model and trim before ordering, and compare the port layout with your existing system.
What’s included
Check the package contents for clamps, hangers and gaskets when it arrives.
