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5W-30 Motor Oil
5W-30 oil is best for vehicles that are regularly driven in colder climates where temperatures can fall below 0 degrees Fahrenheit. It is a light oil that will circulate through an engine faster than a more dense grade. 5W-30 is designed for use in colder climates where cold engine starts are common. It is generally recommended for new and high-mileage vehicles under all weather conditions.
20W-50 Motor Oil
Due to its high-viscosity, 20W-50 is suitable for hotter climates. It is highly recommended for older vehicles. The oil's density helps protect aging engine parts and helps prevent leaks that are common with older cars. It is important to note that 20W-50 oil may be too thick for many newer passenger cars and can cause serious engine damage. Check with an automotive professional before switching motor oils.