Regular or Synthetic Oil? How to Keep Your Car Hydrated

If you're not sure which kind of oil to choose, browse Groupon's rundown of the three main options.

Motor oil is integral to your engine’s performance—it keeps parts moving friction-free, prevents the engine’s temperature from getting too high, and cleans the engine as it circulates. After so many miles on the road, however, oil breaks down. When this happens, it’s up to you to choose the type of motor oil you want to refresh your engine.

Regular, or conventional, motor oil is made from petroleum pumped from the ground. Oil refineries process this crude oil into various thicknesses, with thinner oils reserved for car engines and gas tanks. Unavoidable natural impurities and creepy fossils occur in regular motor oil, which is why owner’s manuals recommend an oil change every few thousand miles as these impurities build up in the form of “sludge.”

Synthetic oil, as the name implies, is the result of manmade processes designed to produce the most efficient lubricant possible. Most synthetics are born from natural oil and then purified at the molecular level. Since its molecules are all the same size, synthetic oil maintains its viscosity better in extreme temperatures than regular motor oil, helping engines purr even in the darkest days of winter. Synthetic oil also lasts longer than its counterpart and can prolong the life of an engine. However, it also costs two to three times more than regular motor oil per oil change.

Semi-synthetic or synthetic-blend oil combines regular and synthetic oils, producing a lubricant with many of the same benefits as synthetic oil at a lower cost. Drivers can also switch between synthetic and regular motor oils without doing damage to their car’s engine.