Getting ready to change the oil in the new to me 300 hp Yamaha outboard. I have been reading about which oil to use. In looking in the manual and based where we live with summer temps in mid 90 and up it says YAMALUBE 4M FC-W 10W-40 In looking for this oil I am not finding it in the 10W-40 range. Finding plenty of 10W-30 oil
What oil are using?
What oil are using?