American corporation engaged in the manufacture and sale of truck trailers. Headquarters are in Indianapolis, Ind., U.S.

The founder, August Charles Fruehauf (1868–1930), began as a blacksmith and carriage builder around Detroit. In 1914, at the request of a local lumber merchant, he built a trailer to carry the merchant's pleasure boat, to be hauled by a Ford automobile. The trailer was so successful that the merchant had Fruehauf build similar haulers for his lumber, which Fruehauf came to call “semi-trailers.” Business boomed, and four years later, in 1918, Fruehauf incorporated the Fruehauf Trailer Company. Over the next few decades the company prospered and introduced several new concepts in trailer design and size—first under the founder and then under his son Harvey Charles Fruehauf (1896–1968).

In 1953 Harvey's younger brother Roy August Fruehauf (1908–65) wrested control of the company but inaugurated financial and tax practices that led to federal indictments and company instability. The young Fruehauf was removed in 1959, but his successors, William Grace and Robert Rowan, while expanding and diversifying the company's operations, also exhibited questionable management practices. A leveraged buyout in 1986 by the company's management left Fruehauf burdened with debt, and in 1989 the company was broken up and sold, though one segment, the truck trailer unit, retained the name Fruehauf Trailer Corporation.