Stroll down the oil aisle of a typical auto-parts store and you’ll be confronted with a literal wall of lubricant. Doz ...

Pennzoil produces a range of conventional motor oils, synthetic blends, and full-synthetic oils, such as its Ultra Platinum, High Mileage, and Platinum Euro lines. Havoline is a motor oil company ...

and “extended life” and “high mileage” conventional oils—may leave you wondering which is the best for your car, even if you’re just getting the oil changed at your local service station.