Light Duty, Medium Duty and Heavy Duty

This is the most commonly used vocabulary in fleet and the least consistently defined, and the disagreement sits between federal sources rather than between careless ones.

• The FHWA class chart groups Classes 1 and 2 as light duty, which puts the boundary at 10,000 pounds GVWR.
• Federal fleet regulation at 41 CFR 102-34 defines a light duty motor vehicle as one with a GVWR of 8,500 pounds or less.
• EPA emissions rules at 40 CFR 1037.801 define a heavy-duty vehicle as any motor vehicle above 8,500 pounds GVWR, and label the 8,501 to 10,000 pound band Class 2b.

So an ordinary three-quarter-ton pickup rated at 9,000 pounds is light duty on the class chart and heavy duty to the EPA at the same time. Both statements are correct. They answer different questions.

For a public fleet this is not trivia. The same truck can sit in the light duty column of an internal inventory report, fall outside a light duty definition in a federal reporting requirement, and be regulated as heavy duty for emissions. When a specification, a grant application, a sustainability target or a fleet report says light duty, the useful next question is which threshold it means, because two people can build entirely different numbers from the same vehicles and both defend them.