I've been running Pennzoil 10W-40 in my '95 Hyundai Accent (to help w/oil consumption this summer) and would like to continue to do so through the winter. The "winter" here never reaches colder than about 40 F -- and that's first thing in the morning. Once daylight hits, it's never colder than 50. Does anyone anticipate any problems with this oil in this weather? The car is driven in a pre-dawn/early afternoon work commute of 30 miles each way. I recently completed a double treatment of Auto-RX with this oil in this car. The reason I wanted to stick with 10W-40 is purely to get a UOA with this brand/grade...since there are none posted on this site. If the UOA wasn't a factor, I'd probably switch back to 10W-30 or 5W-30 in the winter. Hyundai recommends anywhere from 5W-30 to 20W-50 in the manual, with a "preferred" grade of 10W-30. Any harm to sticking with 10W-40 through a mild winter?