Can you use 10w 40 oil in a Toyota Highlander?

Yes, you can use 10W-40 oil in a Toyota Highlander, but it's essential to check the owner's manual for the manufacturer's recommended oil viscosity. Typically, most Highlander models recommend 5W-20 or 0W-20 for optimal performance and fuel efficiency. Using 10W-40 might be suitable in certain conditions, such as higher temperatures or for older engines, but it could impact fuel economy and engine performance. Always ensure that the oil meets the necessary specifications for your specific vehicle model and engine type.