Q: Advice on how long conventional oil can last and how often to change it

You’ve got to realize that it depends on how you drive and where you drive. I personally change my oil in my own car every 3,000 miles because I don’t drive that much. I don’t even drive 3,000 miles a year so I generally change my oil once a year.

If you drive on the highway all the time, you can get away with changing it every 5,000 miles or even 7,500 miles if you do a lot of high-speed driving since you don’t get much wear going at a continuous speed. or example, those big 18-wheel diesel trucks on the highway typically change their oil every 15-20,000 miles, because they are going 65 miles per hour steadily. It really doesn’t wear down the engine much at that continuous speed.

However, if you do a lot of stop-and-go city driving, then it is a good idea to change it every 3,000 miles if you have conventional oil and every 5,000 miles if you use full-synthetic oil.