Product

Diesel Fuel is a complex combination of hydrocarbons produced by the distillation of crude oil. It consists of hydrocarbons having carbon numbers predominantly in the range of C₉ through C₂₀ and boiling in the range of approximately 163°C to 357°C (325°F to 675°F)^[1].

The Diesel Fuel produced by a refinery is a blend of all the appropriate available streams: straight-run product, FCC Light Cycle Oil, and Hydrocracked Gas Oil. The Straight-Run Diesel may be acceptable as is, or may need minor upgrading for use in Diesel Fuel prepared for off-road use^[2].

The diesel pumped at truck stops and used in heavy goods vehicles is standard No. 2-D ULSD (Ultra Low Sulfur Diesel, ≤15 ppm sulphur) in the US, or EN 590 compliant diesel in Europe — both of which are automotive diesel^[3][4][5].

The key distinction is not between cars and trucks, but between highway (on-road) and off-road use:

• On-road / highway diesel — same specification for both cars and trucks, tightly regulated for sulphur (≤15 ppm in the US, ≤10 ppm in the EU), subject to road fuel tax^[3][6].

• Off-road diesel (also called red diesel, marked oil, or non-road diesel) — the same hydrocarbon cut but with a dye marker added, exempt from road fuel tax, used in construction, agriculture, mining, and stationary engines. Higher sulphur limits apply in some jurisdictions^[4][6].

The density of petroleum diesel is about 0.85 kg/l – about 15–20% higher than the density of gasoline, which has a density of approximately 0.70–0.75 kg/l^[x].

Chevron's Diesel Fuels Technical Review is attached for download^[2].

References

1. European Chemicals Agency (ECHA). Substance Infocard: Fuels, diesel
2. Chevron, Diesel Fuels Technical Review (Sep 15, 2007)
3. United States Environmental Protection Agency (EPA). About Diesel Fuels (last updated: Jan 29,2025)
4. Britannica. diesel fuel (Page version: May 13, 2026)
5. Reddit. [Fuel] Difference between "Auto" diesel and "Truck" diesel? (2016)
6. United States Environmental Protection Agency (EPA). Diesel Fuel Standards and Rulemakings (last updated: Dec 2, 2025)
7. Science Direct, Diesel Fuel