It sounds like too many people are still changing their oil way too often. All you're doing is wasting money and time. Hopefully you recycle the old oil or else you're also filling up landfills. Newer engines are manufactured to extremely tight clearances and can go much longer between intervals. If you use synthetic oil and drive at least 10-15 miles so that the engine gets to operating temps , then you can follow Toyotas 10k recommended interval. You never hear of an engine being torn down and finding that the cause of excessive wear is not changing the oil enough. And don't listen to the guys at the quick lube , they'll recommend changing it every 3000 miles which is absurd. If you put on less than 10 thousand miles a year then by all means change it once per year. And of course there are exceptions , such as short trips in cold weather or an Arizona desert summer, or towing. Just research it online if you're not convinced.