In Part 1 of this article, an overview of how August Fruehauf began the Fruehauf Trailer Company was provided. In Part 2, information about the various types of trailers that Fruehauf pioneered are provided. FreightWaves Classics thanks Ruth Ann Fruehauf for her contributions, as well as the Fruehauf Trailer Historical Society for information and photographs that contributed to this article.

Different types of trailers

The following paragraphs provide information on the key types of trailers developed and manufactured by the Fruehauf Trailer Company.

Dry freight vans

Dry freight van semi-trailers are the most common type of trailers on the road. Those manufactured by Fruehauf were modified many times during the 85 years they were produced. There were customized semi-trailers for specific industries with modifications tailored to order. For example, drop-frame furniture vans were manufactured for that industry. 

Images and explanation of dry freight vans. (Photo/text:

Early Fruehauf trailers were made from durable steel and wooden materials, which made them very heavy. However, as the practicality of semi-trailers grew, customers asked for modifications to reduce trailer weight, which allowed more freight to be moved. Early trailers had rounded noses; they had reduced the tendency of trailers to jack knife and also gave tractor-trailers a greater turning radius. However, the rounded nose also meant there was wasted cargo space  in the rounded nose. Therefore, the design was changed to the square-nosed trailers we are all familiar with now. 

A unique looking trailer that Fruehauf designed for Canada's Labatt Brewing Company. (Photo:
A unique trailer that Fruehauf designed for Canada’s Labatt Brewing Company. (Photo:

Depending on the type of freight to be hauled in the trailers, Fruehauf dry freight vans were manufactured from corrugated steel, stainless steel and lightweight aluminum. Fruehauf’s chassis and light wall system gave customers a competitive edge – they were able to carry more freight because of their lighter weight. In the late 1950s, Roy Fruehauf said, “Our large research and engineering department is constantly making improvements and suggesting changes. And we are always trying to increase payload capacity by decreasing the weight of the semi-trailer without sacrificing strength.”

The Fruehauf Trailer Company also developed the I-beam axle, torsion bar suspension, self-lubricating brake lines, and other engineering advances.

Photos and an explanation of dump trailers. (Photo/text:

Dump trailers

Beginning in the 1920s, Fruehauf was the first trailer manufacturer to use hydraulics in freight transport. Lift gates could be raised or lowered for easy loading and unloading. Fruehauf engineers employed hydraulics to create dump trailers – they modified utility trailers so that bulk contents could be unloaded using gravity instead of manpower. Another Fruehauf innovation was equipping trailers with multiple axles; they increased the weight Fruehauf trailers could carry. These innovations and others benefited such industries as mining and road-building that needed to haul heavy loads.  

Photos and text explaining tanker trailers. (Photo/text:

Tanker trailers 

Companies that transported bulk commodities came to Fruehauf seeking an enclosed semi-trailer that was capable of hauling liquids and dry bulk cargo. Fruehauf designed and manufactured the first tank trailer; it was used to haul flour. Expanding on the concept, Fruehauf designed and built tankers for different liquids (such as for milk and other liquid foods), as well as petroleum products and industrial chemicals. 

A key safety issue with tankers was the cargo’s weight; if the liquid shifted during transport it might alter the trailer’s center of gravity and forward momentum. This led Fruehauf to develop smaller compartments within the larger tanks that decreased these issues. Responding to customer needs, Fruehauf tankers were built from different materials, including steel, stainless steel and aluminum. And, because of the numerous liquids transported in tankers, some were insulated, others were pressurized and others were refrigerated.

Photos and an explanation of refrigerated trailers. (Photo/text:

Refrigerated trailers

Railroads began using refrigerated railcars to carry perishables in the late 1870s. August Fruehauf modified the railcar technology to manufacture a semi-trailer that could transport perishable foods in the 1920s. Early models of the Fruehauf refrigerated trailers had a roof  opening through which pulverized ice and salt were dropped onto the cargo to keep it cold. The design of these early “reefers” was modified over the years. For example, front and back vents were added to the trailers; this allowed air to pass over the ice during transit. Another modification was the construction of grooved metal floors; these channeled the water from melting ice to flow to drains in the flooring. 

Photos and an explanation of flat bed trailers. (Photo/text:


Designed to haul boxed or “raw” freight (such as lumber, large pieces of equipment, etc.) that requires a platform but no sides, flatbed semi-trailers were developed. Flatbeds primarily haul heavy loads that require steel reinforcement. Fruehauf flatbeds were built with I-beam axles, heavy-duty brake systems and springs. 

In the 1950s, a number of railroads began the trailer on flatcar concept (also known as “piggy-backing”). Fruehauf flatbeds were used in these early railroad/trucking intermodal efforts. Flatbeds also were utilized for another intermodal freight use – carrying the shipping containers developed by Fruehauf for Malcom McLean. Over the next decade the use of intermodal containers revolutionized the ocean shipping, railroad and trucking industries.

Photos and an explanation of container shipping. (Photo/text:

Container shipping

Intermodal containers were pioneered for use by the U.S. military during World War II. But those containers were too small for commercial use. Following the war, Fruehauf partnered with McLean’s company to modify the concept developed by the military to create the shipping container. Fruehauf engineer Keith Tantlinger developed many of the innovations that led to the standardized intermodal container that has now been used for more than 65 years. Fruehauf hired Tantlinger in 1956; his inventions include “vehicle construction spring-to-axle mountings, the bolster locking head to secure a semi-trailer to a tractor’s fifth wheel, a container coupler and a pivoted draw-bar with lock.” 

Fruehauf Trailer Company designed this vehicle to carry these guns. (Photo:
Fruehauf Trailer Company designed this vehicle to carry these guns. (Photo:

Developing innovations for the military

Many manufacturers developed/manufactured various products for the military during World War I, including the Fruehauf Trailer Company. Then in World War II, entire industries and companies within them converted to the production of military materiel for the duration of the war. During the Korean War Fruehauf again built trailers for military use. 

Of the more than 1,000 patents held by the Fruehauf Trailer Company, over 150 patents were for various military-related products (many of which were adapted for commercial use).  

Fruehauf’s military involvement continued during the Cold War. During the 1950s and 1960s, Fruehauf “developed and manufactured missile vehicles, ground-based and submarine-based missile launchers, transporters/erectors, shipping containers, ground handling equipment, equipment shelters” and other products for the U.S. Army, U.S. Navy and U.S. Air Force. Among them were “systems for the Atlas, Bomarc, Corporal, Falcon, Genie, Hawk, Jupiter, Matador, Nike Ajax and Nike Hercules, Polaris, Redstone, Regulus I and II, Sergeant, Thor and Titan missiles.” 

The company’s Military Products Division also manufactured “5,000-gallon fuel tank semi-trailers and 12-ton semi-trailers” for the U.S. Army. Fruehauf manufactured “15-ton amphibious lighters and reusable metal shipping boxes for the military” at its Fullerton, California manufacturing plant. Fruehauf also manufactured practice recovery spacecraft for NASA’s Gemini missions.

A helicopter delivers an intermodal container to a U.S. missile site. (Image:
A helicopter delivers an intermodal container to a U.S. missile site. (Image:

Packers and movers in peenya Packers and movers in peenya Packers and movers near me Packers and movers near me Packers And Movers Banashankari Bangalore a Packers And Movers Banashankari Bangalore a Packers And Movers Jayanagar Packers And Movers Jayanagar Packers and movers Yelahanka Packers and movers Yelahanka Packers And Movers Btm Layout Packers And Movers Btm Layout Packers And Movers Koramangala Packers And Movers Koramangala Packers And Movers Hsr Layout Packers And Movers Hsr Layout Packers And Movers Bommanahalli Packers And Movers Bommanahalli Packers And Movers Begur Road Packers And Movers Begur Road Local Packers And Movers Bangalore Local Packers And Movers Bangalore Packers And Movers Ramamurthy Nagar Packers And Movers Ramamurthy Nagar Packers and movers Bangalore Packers and movers Bangalore