Heavy duty truck

Truck classifications are typically based upon the maximum loaded weight of the truck (typically using the gross vehicle weight rating (GVWR) and sometimes also the gross trailer weight rating (GTWR)), and can vary among jurisdictions.

In the United States, commercial truck classification is determined based on the vehicle's gross vehicle weight rating (GVWR). The classes range from 1–8. Trucks are also classified more broadly by the Department of Transportation's Federal Highway Administration (FHWA), which groups classes 1–3 as light duty, 4–6 as medium duty, and 7–8 as heavy duty. The United States Environmental Protection Agency has a separate system of emissions classifications for trucks. The United States Census Bureau also assigned classifications in its now-discontinued Vehicle Inventory and Use Survey (VIUS) (formerly Truck Inventory and Use Survey (TIUS)).

Class 2 is subdivided into Class 2a (½-ton) and Class 2b (¾-ton), with class 2a being 6,001–8,500 pounds (2,722–3,856 kg), and class 2b being 8,501–10,000 pounds (3,856–4,536 kg). Examples of vehicles in Class 2b include the Ram 2500, Chevrolet Silverado 2500, and the Ford F-250. SUVs in Class 2b include the Ford Excursion and the Chevrolet Suburban 2500. Class 2a is commonly referred to as a light duty truck, with class 2b being the lowest heavy-duty class, also called the light heavy-duty class.

When light-duty trucks were first produced in the United States, they were rated by their payload capacity in tons (e.g., ½-, ¾- and 1-ton). Over time, payload capacities for most domestic pickup trucks have increased while the ton titles have stayed the same. The now-imprecise ton rating is presently used to compare standard sizes, rather than actual capacities.

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