Same fuel chemically — very different rules. Here's what's legal.
Clear diesel is the standard, road-legal fuel. Road taxes are included in the price, and it's legal for any vehicle driven on public roads — trucks, vans, pickups, cars. If your vehicle uses public roads, this is what you buy.
Dyed diesel is tinted red and sold untaxed for off-road use only — farm equipment, generators, construction machinery, boats, and other equipment that never touches public roads. Because the road taxes aren't included, it's cheaper — but using it in an on-road vehicle is illegal.
The red dye is a tax-enforcement marker. Inspectors (federal and state) can dip a vehicle's tank; finding dye in an on-road vehicle is clear evidence the road taxes weren't paid.
Using dyed diesel on the road carries stiff penalties — federal fines that escalate per violation, plus California penalties and back taxes. It is never worth the risk to save a few cents per gallon. For a fleet, one citation can dwarf a year of "savings."
Cardlock stations (CFN, Pacific Pride) often offer both clear and dyed diesel at the same site, clearly labeled. The rule is simple: on-road vehicle → clear diesel. Off-road equipment can use dyed where eligible. California Fuel Club members get commercial pricing on clear diesel for their on-road vehicles — the legal savings come from cutting retail markup, not from dodging tax.
Clear diesel at member pricing, 780+ CA stations. We never mark up your fuel.
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