Mobil 1 Advanced Full Synthetic Motor Oil 0W-40 helps improve fuel economy and extend engine life for vehicles of all ages better than conventional oil. Its uniform synthetic oil molecules reduce friction and help prevent deposits and sludge buildup. Mobil 1 motor oil provides outstanding engine wear protection and excellent internal engine heat protection and low-temperature capabilities. It supports quick cold-weather starting and ultra-fast protection. The 5-quart motor oil also controls oxidation to prevent oil breakdown. It's the world's leading synthetic motor oil brand, recommended by more car builders, experienced mechanics and used by more NASCAR teams than any other brand of motor oil.