Trucking companies act as the backbone of the transportation industry, and large trucks haul everything from food to electronics to furniture across the country. Thousands of trucks carry millions of goods every day. The top trucking companies earn billions of dollars in revenues while facing obstacles ranging from fuel prices to maintenance costs to labor issues to state and federal regulations.

J.B. Hunt Transport Services, Inc.

Since 1961, J.B. Hunt Transport Services, Inc., has been a leader in the trucking industry. Hunt Transport was among the first companies to adopt the "container trucking" approach, in which containers went directly from ships and trains onto trucks. Hunt Transport also provides tailor-made freight transportation equipment, services and logistical expertise to meet the needs of its Fortune 500 customers. The company netted $6.56 billion in 2016.

YRC Freight

YRC Freight traces its origins to Yellow Transit Company, a bus and taxi company in Oklahoma City in 1924. Yellow Transit later merged with Roadway, the dominant trucking company in the U.S. for decades, and Reimer Express, the leading trucking company in Canada, to form Yellow Roadway Corporation, shortened to YRC Freight. The company's specialty of hauling less-than-truckload freight fills the gap between parcel services such as UPS and FedEx and bigger haulers like Hunt. In 2016, net revenues for YRC Freight reached $4.7 billion.

XPO Logistics (formerly Con-way Freight)

Con-way Freight started out in 1929 as Consolidated Truck Lines, a small regional trucking company, in Portland, Oregon. In October 2015, XPO Logistics acquired Con-way, along with the more than the 400 transportation centers they operated in 21 countries across five continents. When Con-way Freight merged with XPO Logistics, they brought their stellar reputation with them; Fortune magazine named Con-way a "Most Admired Company" in transportation and logistics in 2007. In 2016, XPO reported a 91.8 percent annual hike in revenue to $14.62 billion.

Schneider National

Founder A.J. Schneider bought his first truck in 1935, during the worst part of the Great Depression. Tenuous beginnings didn't portend a tenuous future, though. Schneider National reached $1 billion in revenues in 1992, $2 billion in 1996 and $3 billion in 2004. In 2013, the company brought in $3.35 billion, an increase of nearly 3 percent from the previous year. In 2016, with $4.05 billion in net revenue, Schneider celebrated their 81st anniversary as one of the leaders of the truckload-freight industry, with offices in the U.S., Mexico, Canada and Europe, and was named one of the best companies in America to work for by Forbes.

Swift Transportation

In 1966, the company now known as Swift Transportation started hauling steel from Los Angeles to Arizona and cotton from Arizona back to Southern California. More than five decades later, the company now owns 11 other trucking subsidiaries, operates more than 16,000 trucks and hauls truckload-sized freight all over the U.S., Canada and Mexico. In 2016, Swift recorded $4.03 billion in net revenue.