I've noticed that when I take my 6.7 to the dealer for an oil change they pour 12 litres of oil into the crankcase when refilling. The capacity listed in the owners manual says the capacity is 11.4 litres.When I check the dipstick at home ,it's always at the top of the plastic marker on the wire ,way above the crosshatch marks.Is this a major concern? Should I drain some to bring the level onto the stick?