In my lawn service I run all John Deere ztrs with Kawasaki engines. I run Rotella 30 wt in everything, but most of the new equipment calls for 10w30. I change the oil at 75 hrs with a Napa proselect filter. I trade at 2000 hrs but have 1 machine with 2208 hrs and plan to run her till she blows. The more time I spend on this site I am wondering about the straight 30 wt.