Dexos oil is the only type of oil that General Motors (GM) recommends owners use in their cars, as other brands, which contain different compositions, may cause damage and void warranties. GM, like several other car manufacturers, uses an exclusive oil that combines various properties of other car oils. This special blend works only for cars and trucks with the GM label; vehicle owners with cars using standard gasoline use Dexos1, while diesel-powered vehicles use Dexos2.
Both types of Dexos oil contain the five most recent types of oil that GM has authorized for its vehicles. The Dexos oil blend, like other brand-specific formulas, improves performance of GM vehicles and may even prevent premature wear and damage to internal components, such as the engine. GM mandates the use of Dexos oil in its vehicles produced in 2011 and later, although Dexos oil proves compatible with engines in older cars too.
Both types of Dexos oil may help prevent accumulation of sludge deposits in GM engines and improve cars' gas mileage. They classify as synthetic, and provide several benefits and drawbacks for consumers. Benefits include extending the amount of time drivers can go between oil changes, although these oils cost more than their generic counterparts. Additionally, GM drivers face the risk of having their warranties voided if they use non-Dexos oils, and may encounter limitations in finding Dexos oil.