To choose the right engine oil for a vehicle, consider its performance, how well it runs on its current motor oil and what the owner’s manual suggests. The manual is a good place to start since it gives specifics on what motor oil that particular vehicle operates best with.
If a driver has been using the same motor oil for a while and there are no performance issues, it is okay to keep using the same oil, even if it is different from what the manual recommends. An auto mechanic is another person that can provide recommendations for motor oil. There are also some special circumstances that require using a different motor oil. For example, in extreme hot or cold climates, multi-weight oils are best since they cover different temperatures. Older vehicles do best with single-weight motor oil.