: This is a leading choice for diesel pickup trucks and heavy-duty fleets. It features "Triple Protection Plus" technology to protect against wear and deposits in extreme climates. It is available at AutoZone for $34.99 $25.99.

: This oil helps remove existing sludge and prevent new buildup in older engines. It is a favorite among mechanics for extending the life of high-mileage passenger cars and light trucks. Available at Walmart for $27.97 $24.97.

: Uniquely made from natural gas rather than crude oil, this product is 99.5% pure. It is often recommended by performance enthusiasts for its ability to keep pistons cleaner than required by the toughest industry standards. It is sold at Walmart for $26.50. High Mileage Engine Oils

: Expertly engineered to withstand the intense pressure of modern engines, this oil uses "Fluid TITANIUM Technology" to reduce friction. It claims to provide 10X better high-temperature performance than industry standards. You can find it at Walmart for approximately $27.48. Pennzoil Ultra Platinum 5W-30 Full Synthetic Motor Oil Go to product viewer dialog for this item.

: This synthetic blend is developed in collaboration with major original equipment manufacturers (OEMs). It is designed to extend engine life and perform reliably in both on and off-highway applications. Blain's Farm & Fleet offers it for $16.99 $14.99.