I believe the Lower Unit lube just has a few additives to make it extra sticky and displace moisture in a marine environment that is why it is more pricey than straight 90w.
Actually it is prob. a bit better than straight lube. I know a half a qrt. of Johnson lower unit lube for my bass boat is like $12.00, but I have to use or void my warrenty.
Tim


1952 Chevy Shortbed

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