On Mon, 31 Mar 2008 07:26:58 -0400, "Roger Long"
wrote:

I guess beginning and end of season is fine for most folks. My fuel bill
last year was $420 so, roughly 120 gallons, 120 hours. Even someone who
motors as much as I do should be fine changing just spring and fall.

I would argue that if you change the oil at end of season, changing it
again in the spring is a total waste. The oil does not go bad over
the winter and any small amount of moisture picked up over the winter
months will evaporate after a short time running the engine. If you
really motor a lot, over 200 hours per season, changing it once in
mid-summer would be appropriate.