On Thu, May 27, 2010 at 2:02 PM, Ron Schmittou <firstname.lastname@example.org> wrote:
> What was the year of the changeover - I can't remember.
Calendar year 1995. (some cars really did switch in the middle of the
model year.) But lots of '93 and '94 cars are R134a, depending on the
make and model. GM was using R134a in MY94, but maybe not
universally. A proper change in production requires some
re-engineering of the AC system, to adjust to the slightly lower
cooling capacity of R134a, so it probably wasn't done all at once.
Suggested annual donation $12.96