The MagnaFlow 51859 is an OEM-grade, Federal/EPA-compliant front manifold catalytic converter for the 2.4L Highlander. It uses 16-gauge 409 stainless steel mandrel-bent tubing with a spun body that replicates the factory geometry, and a single laser fusion weld reduces leak points while the compact, low-mass design improves thermal efficiency. The gaskets and hardware needed for installation are included, avoiding the reuse of corroded factory parts, and 308 stainless MIG welds add durability for a bolt-in fit with no cutting or welding. It is emissions-legal on Federal/EPA vehicles in 49 states and is not legal for sale or use in California.
| Type | Manifold Catalytic Converter, Direct-Fit (OEM Grade) |
| Position | Front (manifold, primary) |
| Material | 16-gauge 409 stainless steel |
| Emissions | Federal/EPA compliant (49-state, not legal in California) |
| Quantity | 1 |
| Part Number | 51859 |
| OEM Replacement | 25051-28290 |
This part fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2004-2007 | Toyota | Highlander | Base |
