We design Street Legal SAE 5W-30 Synthetic Blend (GF-6) motor oil with a proprietary blend of conventional and synthetic base oils. It features a state-of-the-art additive system to deliver trusted engine protection and peak vehicle performance. Our SAE 5W-30 synthetic blend oil provides added resistance to sludge formation and varnish deposits during stop-and-go driving. It also maintains outstanding wear protection under severe driving conditions. Learn about oil viscosity and why it's the most important physical property of motor oil.