Engine oil is available for purchase in most department and automotive stores or online on websites such as Walmart, Amazon and Mobil. The three main types of engine oil are mineral oil, synthetic blend oils and fully synthetic oils, according to Patrick E. George for HowStuffWorks.
Each car requires a specific type of oil, which is usually listed in the owner's manual, states George. Cars with over 100,000 miles can benefit from using engine oil specifically formulated for high-mileage engines. Synthetic oil is more expensive than mineral oil. Newer cars usually do not benefit from using synthetic engine oil as much as an older car, so consumers should refer to the engine oil recommendation in the owner's manual to avoid wasting money. Mineral oil is made from refined crude oil and works well for most standard vehicles. Synthetic blend oils are recommended for older or high-performance engines as they offer more lubrication and longevity than mineral oil.
Automotive stores such as Mobil sell engine oils online or in the store, as seen on the Mobil website. Mobil also offers online recommendations on the type of oil to purchase based on the year, make, model and engine type of the vehicle. Mobil offers a variety of synthetic, conventional and high-mileage engine oils. Consumers can use the store locator on the Mobil website to find nearby locations.
Department stores and websites, such as Walmart and Amazon, also offer engine oil products. The engine oil category page on Amazon filters products by the type of oil, brand and size. Walmart also offers engine oil products online, which are available for shipment or in-store pickup.