A lot of people seem to be talking Mobil 1.  I have been using Castrol 5-50
since my fourth oil change on  AVP rebuild 2.0 A/C (dino for the first two and
mobil 1 the next two)  Can't beat it for start-up, allows a fast crank in cold
weather, no problems hauling friends up into the mountains or to the beach,
and after I switched, I noticed the engine was a bit quieter on the highway.

Question:  Any one have any knowledge about acidification of synthetics in
vechicles that don't get driven very often, every seems to be talking mileage
on this thread.  Scoff if you will, but I change it every 3000 miles, which
ends up being about 3X a year.

Patrick