Diesel fuel quality information, ultra low sulfur


High quality diesel to get you where you’re going.
Our diesel fuels are blended to provide good ignition quality and are held to high quality standards for our consumers. Their low-temperature fluidity characteristics can also help keep vehicles moving in colder temperatures. Our Ultra Low Sulfur Diesel Fuel is made to meet the needs of the most demanding customers. This diesel fuel is formulated for use in any diesel-fueled vehicle on the road today.

Less energy, better fuel economy

Diesel fuel requires less energy to produce than gasoline. Because diesel has a higher energy density it provides better fuel economy compared to gasoline.

Reliable operability in cold temperatures

We blend base diesel fuel according to seasonal specifications. Refineries provide diesel fuel to geographically cold climates from lighter distillates and use additives to maintain cold weather fuel performance. Cloud point depressants, for example, suppress the temperature at which paraffin waxes form. In especially frigid climates, cold flow additives may be used to help prevent wax crystals from interfering with the engine’s fuel filter.

FAQs about diesel fuel

A modern diesel engine is calibrated to inject the amount of fuel necessary to complete combustion across a range of power outputs. White smoke can be temporarily present during startup, particularly in wintertime, as unburnt fuel mixes with exhaust. The presence of black sooty smoke is an indication of mechanical problems resulting in incomplete combustion. More specifically, sooty particulates are generated with non-ideal atomization of diesel fuel resulting in a fuel-rich combustion atmosphere. Newer vehicles equipped with diesel particulate filters greatly reduce the presence of this smoke.
Ignition quality relates to a diesel fuel’s cetane number – a measure of how readily the fuel auto-ignites under compression in the engine’s cylinder. In the United States, the minimum cetane number requirement is 40 which ensures good ignition quality, ease of start-up, and smoothness of operation in modern diesel engines.
Low temperature operability is the ability of the fuel to flow through the vehicle’s fuel system without plugging filters at low temperatures. Since diesel fuel contains paraffin waxes that may become solid at colder ambient temperatures, the cold flow properties of diesel fuel can be estimated with filterability tests and by measuring the cloud point temperature. To help address this problem, modern diesel engines are designed to warm the fuel pump and filter with engine heat.
Fuel contamination by water and dirt may cause poor diesel engine performance. Extreme care must be exercised when storing and handling fuel. Fuel-tank caps, dispensing nozzles, and hoses should be kept clean to eliminate potential sources of contamination. Fuel injectors and pumps are especially sensitive to wear and abrasion from particulate matter in fuel. Regularly removing water from storage tanks, vehicle fuel tanks, and filter bowls is important. Dry storage systems help reduce fuel emulsion problems, injection system corrosion, and microbial growth.
If you keep it clean, cool and dry, diesel fuel can be stored for six months without significant quality degradation.
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