We have seen galling as well, but only a few times. Like Dennis points out,
it is largely dependent on the type of stainless fastener and what you use
for locking/anti-seize.  A good locking fluid is tricky on exhaust as it
will usually burn off. We switched to mild steel exhaust header to downpipe
nuts, and we use nord-locks for locking as they are the best solution for a
high transient temps and thermal expansion combined when also dealing with
fully coupled engine vibration. Check out the post about them and the
nordlock video:

http://bostig.net/index.php?option=com_content&task=view&id=26&Itemid=2

Jim

-----Original Message-----
From: John Reddick [mailto:SVYOLO@YAHOO.COM]
Sent: Saturday, April 21, 2007 7:47 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Source for Stainless Exhaust Hardware?

SS nuts and bolts on exhaust will still have to be cut off after a short
time due to galling. We did it once after 500 miles.  Every single nut and
bolt was galled and seized.  Every one.

John
Vanaru.com