Re: Opinions on oil types for '03 4 cycle 40 HP Merc?
I based that on the packaging we have on all the oil we just got in. The only bottles with FC-W on the labels were Yamalube. Old stock from the others I suppose. Some have a "Marine Grade Lubricant" on them, but not FC-W. I imagine there's a whole lotta oil that needs to get used up before the new labels get around.<br /><br />Rearding the difference, marine applications usually run much cooler, especially outboards. I expect the marine grades allow for that and the increased environmental moisture content inherent in a marine atmosphere. I imagine that, like marine gearlubes, water content is a big factor that automotive oils just don't have to deal with. Not to mention full-throttle operation for long periods.