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10W-40 motor oil
The 10W-40 viscosity has all but disappeared as a primary recommendation for newer vehicles, and today serves as an alternate choice. Higher viscosity oil such as a 10W-40 can be useful for older engines burning or leaking oil.
We offer Mobil™ 10W-40 high viscosity motor oils for use in vehicles with more than 75,000 miles, and a synthetic blend oil when cost is a consideration.
What do the numbers in 10W-40 mean? The numbers refer to the weight and thickness, or viscosity, of the oil. Motor oil gets thicker when it’s cold and thinner when it heats up. The first number indicates the viscosity of the oil at a cold temperature, and the second number indicates the viscosity at operating temperatures.
Compare to see different levels of protection these products offer and choose the one that meets your needs.