I happened to notice while looking thru operators guides that there is a difference in engine oil capacities in the 2013 and 2018 Commander 800 operator guides. 2013 shows 2.3 quarts and 2018 shows 2.1 quarts. Almost a 1 cup difference (6.4 oz.). Is there a difference in the engine assemblies thru the years? Acefire? Boogerhead? Anyone?