[rotorwrench]

The Ford 259 series was used for a long time in cars and pickups depending on the engine application. The design came from the 1948 change over from the torque tube drive to the open drive shaft set up that lasted till 1951. Borg Warner may have had a fair hand in the design and some production but it's hard to say how much. The overdrive set up was Borg Warner but BW also added ODs to several other manufacturer's designs such as the GM Saginaw and others.

Ford changed the gear design for their light duty transmission in 1951 to use the later diamond pattern gears with new ratios. After 1953, there were more and more engine applications that required more strength plus Ford always hedged their bets against production shortages. This is likely why they started using the T86 top loader design as well as the improved 259 design. Ford Likely made a lot of their own castings & parts as well as subbing out parts to companies like Borg Warner to insure no production shortage.

Borg Warner had an exclusive 5-year contract with Ford for the manufacture of the Ford-O-matic design automatic transmissions beginning in 1951. This is why other manufacturers didn't use them in that time frame. They also supplied them a lot of clutches. Ford made what they could and subbed out the rest.

Ford also made heavy duty 3-speeds but they are big and mostly for larger pickups & trucks