Royal Purple SAE 5W-30 Motor Oil delivers superior protection and improves performance in four-cycle gasoline and diesel engines. It increases horsepower and torque, saves fuels and reduces heat, wear and emissions. It has unsurpassed oxidation stability that allows for extended oil drains and fewer oil changes, which saves you time and money and reduces the impact on the environment. Royal Purple’s performance advantages come from a blend of synthetic oils plus Royal Purple’s proprietary Synerlec technology. Sold by the quart.