409,000 Miles Without an Oil Change Using AMSOIL Synthetic 15W-40 Heavy Duty Diesel and Marine Oil this 1990 Mack E7-400 owned by Haywood Gray went 409,000 Miles Without an Oil Change !! Read how

Performance, Protection, Fuel Economy and Convenience!

You can't buy better protection for your hard-working diesel truck than AMSOIL synthetic motor oil. Whether you want the fuel economy benefits and ultra-cold temperature protection of a diesel-formulated 5W-30 or the tried-and-true protection of a 15W-40, you just can't beat AMSOIL synthetic motor oils.

AMSOIL Series 3000 Synthetic 5W-30 Heavy Duty Diesel Oil
In a head-to-head comparison, Series 3000 provided better wear protection than Delvac 1, Delo 400, Rotella T and Cummins Premium Blue (see chart). Independent laboratory testing shows up to 43 percent less wear with Series 3000 than with the other oils tested.

Series 3000 also offers 12 TBN protection for serious long-term acid control and a stay-in-grade formulation to protect moving parts from high-temperature contact and wear throughout the oil's service life.

Series 3000 is formulated for significant fuel savings, boosting fuel economy far beyond what it would be with a conventional 15W-40 oil. For easy cold temperature starting and dependable cold temperature protection, Series 3000 can't be beat. It's ideal for northern tier diesel owners.

Series 3000 is formulated for gasoline engines, too, making it the ideal motor oil for multi-vehicle households or fleets.

AMSOIL 15W-40 Oils
AMSOIL Synthetic Heavy-Duty Diesel and Marine 15W-40 Motor Oil and AMSOIL Synthetic Blend 15W-40 Motor Oil have been put to the test over millions of miles in heavy-duty trucks.

They are proven to provide unsurpassed engine protection, even when they are used much longer than conventional diesel oils are used.

AMSOIL maintains its protective TBN and viscosity while petroleum oils rapidly lost both. More to the point, AMSOIL keeps engine wear rates low. And isn't that what
motor oil is all about?