Green Earth Technologies (1627) G-OIL 15W-40 Ultimate Biodegradable Synthetic Blend Motor Oil - 1 Quart Bottle Ultimate biodegradable G-OIL synthetic blend motor oil provides superior protection under the toughest driving conditions, during the maximum oil change intervals recommended by vehicle manufacturers Safe solution for all diesel engines requiring conventional or synthetic motor oil G-OIL is compatible with all other motor oils API CJ-4/SM approved Grown and made in USA