Hello everyone, today when I started up my 4Runner it was vibrating pretty bad and it slowly went back to normal. Everything seemed fine but it did it once more at a stoplight. Pretty hefty vibrations. I had refilled it completely with gas on Saturday and drove 2.5 hours to Chicago that night from Iowa. Didn't drive it yesterday and today when I went to start it up it was vibrating pretty bad. Other than that everything seemed normal. Any ideas? Could it be the mixing of BP, Shell, and Costco gas that I do?