What's the 2013 hyundai sonata oil drain plug size?

Your 2013 Hyundai Sonata will have an oil drain plug where the hex head measures either 16mm or 17mm, depending on the oil drain plug used. It can and will accept both. If memory serves, the manufacturer's drain bolt measures 16mm, thougH17mm aftermarket replacements are more common. When replacing the oil drain plug, it's always best to replace the crush washer, and it's imperative that You torque to specification. Specifically, on the '13 Sonata, You'll need to fall in the 25-33 lb-ft range. Too loose and You run a significant risk of oil loss; too tight and You run the risk of damage to the delicate drain plug, or the aluminum oil pan. If You don't have access to a torque wrench, You may want to borrow one for this specific application.