I had to set my mind at ease about "oil gelling."
My 2002 Sienna has 38,000 miles, using Chevron Supreme 10W-30 in summer, and 5W-30 in mid-winter, averaging about 2000 miles between oil changes. On my 2 long trips to Florida, I used Mobil-1 10W-30. I use 93-octane fuel, and drive about 60/40...