Our on-line store is open 24/7 and we ship Monday through Friday, excluding some holidays. Orders received for products without shipping restrictions on its product page will ship the same business day when received before 12:00 p.m. PST. Orders in high demand will have an estimated production time listed on its product page and will ship according to the date listed.
Yamalube 10W30 Outboard Mineral 4M FC-W Marine Engine Oil Quart
Yamalube 4M is a mineral-based four-stroke outboard engine oil that's an approved NMMA FC-W formulation specifically for use in the harsh marine environment. The FC-W rating, which sets the minimum standard for outboard engine lubrication, corrosion protection, and resistance to potentially harmful effects of oil dilution caused by fuel, provides critical assurance that your outboard's oil meets the minimum. Go it one better. Yamaha's exclusive and proprietary additive package means Yamalube 4M meets or exceeds the industry standards for lubricity and corrosion protection.
Automotive engine oil will not pass the rigors of the FC-W test. In fact, most automotive engines cruise at 2500 rpm, whereas an outboard can typically operate from 4500 to 6000 rpm all day long. That kind of stress will literally tear automotive engine oils apart. Simply put, an automotive oil is not designed or formulated to provide the protection required by an outboard's moisture-rich, high-rpm, high-load environment.
Go with Yamalube 4M.
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