I'd be interested in knowing if anyone has tried to replace their R-12 A/C
systems with R-406a or Autofrost instead of doing a R-134a conversion.

This stuff looks good, because it is compatible with R12 oils and seals, and
has been EPA approved for use in vehicles as of 1996. It is reputed to have
an efficiency BETTER than that of R-12, let alone R-134a which is known to
have poor heat exchange qualities comapred to R-12.

I've been looking at www.aircondition.com and www.autofrost.com.

I'm different from the standard Vanagon user in that I have a BEHR in-dash
A/C, which I have no hesitation in suspecting is currently using R-12. Since
R-406a is a drop-in replacement for R-12 I'm much more inclined to try this
path than baulk at the cost of an R-134a retrofit or conversion.

The only down side is that since the unit cools a whole lot better, it also
heats up at the condensor a whole lot more too. Reason to be sure you've got
the post-1986 Thermo-switch to be sure that you're fan cuts in at sub 100c
temperatures.....

So, if anyone else has any experience with R-406a or Autofrost, I'd like to
hear it.  Otherwise, I'm about to embark on a 3 week
SoCal/Nevada/Arizona/Utah tour that might cause me to find an R-406a dealer
en-route and have the thing gassed during the trip.

Of course, I'd offer my feedback to y'all in case it turns out to be a
worthwhile discovery. (As an expat Aussie, it just kills me that I get to
use y'all in a sentence once in awhile....!)

Luke Plaizier