Hyundai engines are not picky about oil viscosity and will run just fine on any (temperature appropriate) grade, synthetic or conventional, but will sound a lot less like a half empty Pringles can with a 30 or 40 grade. 0w is just fine as well but probably not necessary unless you're driving it through Canada or Alaska in the dead of winter.Hello just got a Used 2008 Elantra. Will be doing an oil change. The manual recommends 5w20 or 5w30 they even had a 10w30 on the chart but was not recommended for best fuel economy. This car has less that 60,000 miles on it. I will be running synthetic. Is it wise to consider a 0w 20 or 30 weight for this engine. I was considering Valvoline,Quaker-state and even Super tech. any suggestions on a oil grade or brand would be helpful.