Toyota 4Runner, Tacoma and FJ Cruiser 4.0L V6 Manifold Catalytic Converters Guide
Reviewed 2026-10-03. Checked against the sources listed below. This is general information, not a substitute for a mechanic's inspection.
Quick answer
On the 4.0L V6 in the 2003-2009 Toyota 4Runner, 2005-2011 Tacoma and 2007-2009 FJ Cruiser, the catalytic converters sit right at the engine as part of the exhaust manifolds, one for each side. A crack in the manifold section or a failed converter means replacing the manifold converter for that side, not just a pipe. Common signs are a ticking sound on cold starts, an exhaust smell, and P0420 or P0430.
Exact fit
| Years | Make | Model | Engine |
|---|---|---|---|
| 2003-2009 | Toyota | 4Runner | 4.0L V6 |
| 2005-2011 | Toyota | Tacoma | 4.0L V6 |
| 2007-2009 | Toyota | FJ Cruiser | 4.0L V6 |
4.0L V6 only. The 4Runner and Tacoma were also sold with other engines that use different exhaust parts. Confirm Displacement (L): 4.0 and 6 cylinders in the free NHTSA VIN decoder.
Why manifold converters are different
On many vehicles the converter sits further down the pipe. On this engine, each converter is joined to its exhaust manifold, so it gets hot fast after a cold start, which helps it clean the exhaust sooner. The trade-off is that the manifold section goes through big heat swings every drive, and that is where cracks and leaks tend to start.
Signs one side is failing
- Ticking or puffing on a cold start that fades as the engine warms
- Exhaust smell in the engine bay or cabin
- P0420 (bank 1 side) or P0430 (bank 2 side)
- Black soot around the manifold flanges
- Rattle from the converter area with the engine off and cold
One side or both?
The AFECO 51326/51327 is sold as a set for both sides. If only one side has failed, the other side has seen the same years of heat, so many owners replace both at once to save doing the job twice. If you only have one code, that side is where to start your checks.
Is there a recall?
We checked NHTSA's recall database for every model year on this page. None of the safety recalls listed involve the exhaust system or the catalytic converters. NHTSA's system returned no complaint data for the 2010 Tacoma, so check your own VIN at nhtsa.gov/recalls.
Before you replace them
- Fix misfire or fuel trim codes first.
- Rule out a leaking gasket or broken stud at the manifold, which can tick without the converter being bad.
- Test the downstream oxygen sensors.
- Plan for seized studs: soak them with penetrating oil, and have replacement studs and nuts ready.
