The 2010 Hyundai Sonata generally requires SAE 5W-20 motor oil, in either a conventional or synthetic-blend form. The exact grade can vary by engine and climate, so it’s best to confirm with the owner's manual or the under-hood label on your specific car.
For the 2010 Sonata, Hyundai offered at least two engine choices, and the oil specification is designed to protect both. In most cases, 5W-20 is the standard viscosity, and the oil should meet API SN or a newer specification. If you operate in extreme temperatures or if your vehicle has a service bulletin or unusual maintenance history, an alternate grade may be permitted only when specified by Hyundai. When in doubt, follow the official documentation for your vehicle.
Where to verify the exact specification for your vehicle
To ensure you’re using the correct oil, check the lubrication section of the owner’s manual and look for the viscosity and specification on the engine oil fill cap or the driver’s side door jamb sticker. If you don’t have the manual, you can obtain a PDF from Hyundai’s official site or contact a Hyundai dealership for your specific VIN.
Why the right oil matters
Using the correct oil grade helps protect engine bearings, maintain proper lubrication across temperature ranges, and support fuel economy and emissions systems. Using the wrong viscosity or an oil that doesn’t meet the required specification can lead to increased wear and reduced performance over time, especially in extreme weather.
Summary
For the 2010 Hyundai Sonata, the typical requirement is 5W-20 engine oil that meets API SN or newer, with synthetic or synthetic-blend options common. Always verify with the owner’s manual or vehicle label and follow Hyundai’s recommended maintenance intervals to keep the engine running smoothly over the life of the car.