This is what I saw first as well...

 

Good catch...the flange replaces the washer...

 

My exhaust does not show any rust. Is it just surface rust?
So far my exhaust looks good at 65k on the4 2012.


My 2009 still show no rust. Must be California.


Donovan

 

Personally, I wouldn't have a problem using stainless if it's just because of the lower strength. We're talking about an exhaust pipe that has minimal movement and very little sheer stress. Even in the picture showing the bolts broken the two exhaust sections moved very little.

What I don't know is how well stainless steel handles heat cycles, but my understanding is it may only reduce the metal's oxidation resistance if you use 304 vice 316. We're only talking max temps of mid-1200's, which is well below the max temps of SS.