'04 V70 2.4NA - Any issues with swapping catalytic section with '05 2.4 NA?

[jrschwit]

I presume no issues with physical fitment but will verify before beginning work. But what about potential oxygen sensor issues? I gather that these cars are so specifically programmed that I'd like to confirm no sensor compatibility issues beforehand. Presumably, I can swap O2 sensors into donated cat.

'04 car runs fine; simply a very loud and annoying rattle coming from converter. Thus the swap.

[jonesg]

Pull off and investigate the cat, maybe the hanger bracket came loose. I welded mine back in place 2 yrs ago.

[MossieMurphy]

You can do this swap if you are using an O2 sensor from a 2004 vehicle and verify that the size and location of the sensor have not changed.

[DavidE7]

I put a cat from a 2007 S60 2.5T onto a 2004 XC70 2.5T and it fit fine in the front for the turbo and primary oxygen sensor but there were two problems in the rear. First, the downstream oxygen sensor needed a 6 inch extension cord because it was in a different position compared to the earlier P2s. Second, the angle of the flange for bolting the front to rear exhaust systems was different. I welded an angle adaptor from a very short section of junkyard exhaust pipe, used two gaskets, one on each side of the adaptor, and longer stainless steel bolts for holding the four flanges together. Unfortunately I didn't take a picture. Later I realised I should have checked IPD or FCP for catalytic converter and exhaust system compatibility.

[chrism]

Compare Volvo’s part numbers for both years. If it’s the same number than I would think you’d be good to go.

[jrschwit]

I wrote the OP before lifting both cars and carefully checking things over. It turns out the upstream O2 sensor is in the exh manifold so it stays with the car. And the downstream sensor is in the same location on both cars so I'll just replace the piping and keep both original sensors in the car,

The better news is, at least for now, that the noise has stopped. So I'll defer the swap until it reappears but at least I'm ready if it does.

Thanks to all for the comments.