Development of the TOP TIER ^TM Diesel Standard

The TOP TIER^TM Diesel fuel standard was first established in 2017 to promote better fuel quality in marketplace to address the needs of diesel engines. It provides an automotive recommended fuel specification to be used in tandem with regional diesel fuel specifications or regulations. This fuel standard was developed by TOP TIER^TM Diesel Original Equipment Manufacturer (OEM) sponsors made up of representatives of diesel auto and engine manufacturers. This performance specification developed after two years of discussions with various stakeholders such as individual OEMs, members of Truck and Engine Manufacturers Association (EMA), fuel additive companies, as well as fuel producers and marketers. This paper reviews the major aspects of the development of the TOP TIER^TM Diesel program including implementation and market adoption challenges. Various fuel properties of concerns from OEMs perspective are discussed, and details of the TOP TIER ^TM Diesel standard, including the test methods and corresponding limits, are described.