In a message dated 29/04/2009 6:48:03 P.M. Central Daylight Time,
LISTSERV@GERRY.VANAGON.COM writes:

I have  read that the perception that a synthetic oil has detergents,
which damage  seals is an artifact from the synthetic oils of 15 years
ago.  Most  articles seem to say that current synthetics won't degrade
your  seals.  I would be curious to hear if there are people who  have
experienced leaks in the last 5 years that strongly correspond  to
switching to synthetic oil.

Its also really useful when people  include the temperatures that their
vehicles operate when giving oil  suggestions as this helps put the
recommendation in perspective.

My  goal is to find a synthetic oil that is the best weight for Seattle
(Summer  highs of 90 and lows of 50 and winter highs of 55 and lows of
25) that also  includes some sort of zinc content.  Any  suggestions?