I have the same problem on my XF, its down at the local dealer getting a new 3-way cat fitted under warranty. Cost is @ £800 (@$1600)

 

Converters do not go bad NO MOVING PARTS

something causes them to have failure .

antifreeze - raw fuel lite off in the Converter - Damage

you need to find out what caused the failure

 

dealer said it was bust - it rattled every time i set off at low revs - all fixed and no more rattles

 

I'm going to make them give me the original converter to inspect. This car sat on the east cost for a long time, then on the Dealership in Texas for almost a year. Likely it was cold-started and run a few times. Raw fuel in the converter can rot it out, that is likely the cause.

 

Did anyone ever come up with the part # for this piece?

 

Is this type of set up something specfic to European Crossfires ?

 

Since no one seems to be able to follow links on this forum...

Taken from here:

 

Thanks, I actually figured it out today with the help of Mercedes. Apparently my dealer did not have a parts breakout showing the SRT-6 specific parts, so they had the right part all along but thought it was wrong because they had never worked in an SRT-6 exhaust before, and the illustration showed the setup for the standard model, which is very different. To make matters worse, they don't have my car so they couldn't just look and see.

At any rate I'm all set now. Also, the parts match the Mercedes SLK32 parts, as expected and I now have the Mercedes cross-reference for these. I'll post them here tomorrow after I get them off my desk at work so if anyone needs to replace them out of warranty they can just order the parts from Mercedes. They are $1,450 per side from mercedes, but $2,300 from Chrysler. The dealer did verify the matching Mercedes part numbers stamped in the side.