There should be a "severe" and "normal" schedule outlined in your owner's manual, never trust a sales person as far as you can throw them. Just follow the manual, you should fall under one of the categories mentioned earlier. "Severe" is defined as driving in stop-and-go situations, towing or driving in dusty conditions. "Normal" is driving mostly highways. I say if you fall in between the 2 categories then follow the "severe" schedule. Toyota "engineering" says follow your owner's manual, that's why it comes with the car.