The weight rating.
This depends on where you are. Where I live (Alberta Canada) Heavy trucks go the same speed as cars. England heavy goods vehicles run 90 kmph max or 100 kmph max depending.
the 2500s have higher torque, a bigger frame and are more heavy duty overall
AB Volvo, which owns Volvo Trucks, Mack Trucks, Renault Trucks, UD Trucks (formerly known as UD Nissan Diesel), and others.
Peterbilt trucks are manufactured by the Peterbilt Motors Company. The company, founded in 1939, was named after founder T.A. Peterman and sells medium and heavy duty trucks.
The truck auctions feature medium-duty and heavy-duty trucks, as well as trailers. They include trucks manufactured by Peterbilt, Kenworth, Mack, Freightliner, International, and Volvo.
Allison transmissions are often mated to Cummins engines in medium- and heavy duty trucks.
For brand new heavy duty trucks, try Heavy Duty Trucks USA. Trucks Junction and 1 Used Trucks both sell used heavy duty trucks online for a cheaper alternative.
Peterbilt is the luxury class of heavy duty trucks. Custom Peterbilt refers to the ability for the buyer to customize the truck per the buyers specifications.
One can purchase a used commercial truck by going online to the site of Market Book. There are different types of trucks available: heavy duty truck, medium duty trucks, and light duty trucks.
The dodge D100,150,200,250,300,350 are all medium/heavy duty trucks which were produced as 2wd trucks, the power wagon badge was placed on those d100-350 trucks which came with 4x4 or full time 4x4.
I would advise you to check out Commercial Truck Trader. They offer listings for new and use heavy duty big sleeper trucks, along with light and medium duty trucks. They currently have over 62,000 trucks listed for sale! Check it out at: http://www.commercialtrucktrader.com/
A "Big" truck is a non-technical term. It can mean a large pickup, or a semi-truck. Trucks are classified as light medium and heavy.