was running my 290 last weekend a bit and it seemed to not use as much bar oil between gas refills. maybe 1/3 of a tank of oil to a tank of gas. it was cold as hell and i noticed the jug i was using said it was summer weight. saw seemed to cut ok but i only ran two tanks. i honestly never noticed there was a different types before but i guess it makes sense, viscosity, etc. i usually do my cutting in warm weather. i went out and bought another jug but couldn't find "winter weight", just all purpose. do any of you change it up in the winter or just dump and go like me?
