Gulf Supreme Duty XLE series are extra high performance diesel engine oils specially developed for use in modern, high-output, low emission engines meeting US 2007 on-highway exhaust emission standards. These oils not only addresses the unique needs of these new engines and enhances the life of exhaust after treatment devices but also provides improved protection to older engines. These are formulated with state-of-the-art additive technology and severely hydroprocessed base oils to provide outstanding performance and overall protection. It exceeds the performance requirements of API CJ-4 and major global OEMs.