I was reading in the owners manual and recommends 10w30 but you can use 30wt above 50 something degrees which I won't be mowing in that cool of weather. I used mobil super 10w30 and purlator filter I've got bout 10 hours on the oil and it's down middle ways on dip stick. I'm think about putting a 30wt oil either supertech or kohler oil.which would you use or keep what I got in it? Thanks