tech

In some engines a 0w20 is used to help with gas mileage when a 10w30 will work just as good and help the engine live longer . I've seen this at work . I work on a very large fleet of cars and trucks many with very high miles . most oils are of good quality , it needs to be changed often and a good filter used that will help keep it clean . I think that is one of the most important things .