Synthetic is a little more expensive, but when compared to the cost of major repairs to your engine, it’s dirt cheap, really.

(Older cars are more likely to call for conventional oil and synthetic blends.) Any motor oil will ... or dots to denote “full” and “add oil.” If the level falls between the two marks ...

Read more: 15 Popular Oil Filter Brands, Ranked If you're using a synthetic blend, which is a mixture of conventional and synthetic oils, you should change it every 5,000 to 7,000 miles.

One reason why Audi oil changes cost more than those for cars from American brands is that Audi engines need more expensive grades of oil and it must be synthetic or synthetic-blend oil.