I changed my oil this past week at just 90 miles shy of the 600 mile change. The honda oil was looking pretty dirty so I drop the oil and filter and put in Amsoil 10w/30. This oil is stated for use in honda atvs and utvs? So far I can tell that the engine seems to be smoother and alittle more quite. The shift points are definitly far smoother. I also changed the front a rear diffs to amsoil severe gear. Still get the chatter out of the rear when coasting.....maybe a heavier grade would settle thing down?