[Miketadkins]

I know the 4 wheel drive has a set of cats on it, the 2 wheel drive does not. Has anyone ever attempted to swap out the 4 wheel drive for the 2 wheel drive header

 

[jdmartin]

That's the first time I believe I've ever heard that - I thought all Titans had primary and secondary cats. I see that Courtesy lists different part numbers for 2WD and 4WD on that part of the exhaust but I didn't think/know that it had anything to do with cats but rather working around the 4WD structures (transfer case, axles, etc).

Even if that's the case, not sure I can see the value in this unless you happen to have a set of free 4WD pipes that you want to put on your truck. You could hollow out the second set of cats if they do exist that way, but the manifold itself is the thing that cracks on these trucks.

 

[nightowl]

All Titans except the 2004-2006 2wd only have 4 cats. 2 primary manifold cats which are the same on all years and 2 bpipe cats which are the same all years as well. The 2004-2006 2wd bpipes have resonators instead of cats. There is no difference in 2wd or 4wd from 2007 on.