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Ford "X" Transmission
Manufacturer Ford Motor Company
Also called Ford-O-Matic
Production 1958-1981
Body and chassis
Class 3-speed automatic transmission
Related C-4/C-5
Successor AOD

Ford-O-Matic was the first automatic transmission widely used by Ford Motor Company.[2] It was designed by the Warner Gear division of Borg Warner Corporation and introduced in 1951 model year cars. In contrast to Detroit Gear Division's three band automatic originally designed for Studebaker which became superseded by this unit, a variation of Warner Gear's three-speed unit named Ford-O-Matic continued to evolve later into Cruise-O-Matic named transmissions in 1958 and finally the FMX[3] named transmissions in 1968. This line continued in production until 1980, when the AOD was introduced. Like Ford, variations of this same Borg Warner design were used by other automobile manufacturers as well, such as AMC, International Harvester, Studebaker, Volvo and Jaguar, each of them having the necessary unique adaptations required for the individual applications.


In 1948, Ford realized it was late in introducing a fully automatic transmission to its automobile lineup. Ford Engineering Vice President Harold Youngren, recently hired away from Borg-Warner, recommended that Ford license and build a transmission using a design he was working on at his previous employer. Ford and Borg-Warner signed a contract in 1948 which entered B-W into a supply agreement wherein they would build half of Ford's transmissions for five years, with the other half either being built by Ford or by a different supplier. Because of this agreement, Ford licensed the design themselves and broke ground immediately on an assembly plant to build the remaining transmissions. The new plant, called Fairfax Transmission Plant, was dedicated in 1950. The original Ford-O-Matic accomplished two things that Ford's two previous automatic transmissions failed to do. Through the use of an integrated torque converter and planetary gearset, Ford's automatic shifted smoothly without an interruption in torque from the engine. The other was the shifting pattern, revised from PNDLR to PRNDL, which served to reduce "shift shock" when changing gears and reduce "torque shock" when trying to rock a stuck car back and forth. The original Ford-O-Matic, while capable of three forward speeds, started out in second and shifted to third, with first only being used when selecting L on the gear shift column.[4] However, if floored from a standing start, it would immediately shift from second to low then shift back to second and then third as the vehicle accelerated. The Ford-O-Matic was manufactured from 1951 until it was replaced by the C4 in 1964.[2]


In the mid-1950s, cars began to grow in size, and in response to heavier vehicles, more powerful engines were being developed. The original Ford-O-Matic was used as a template when developing the next automatic transmissions for Ford; in fact, many of the gear sets are interchangeable. The new transmissions arrived for model year 1958 which coincided with the release of Ford's new FE and MEL engines. Although marketed as Cruise-O-Matic, the new transmissions were known internally as the MX (larger) and the FX (smaller). They were a three-speed design using a Ravigneaux planetary gearset like the original, but moved the pump from the rear to the front of the transmission, while also using a different valve body so the transmission would start in first gear as opposed to second. The MX was built in the Livonia Transmission Plant in Livonia, Michigan and was placed behind the more powerful engines in Mercury, Lincoln, and select Ford models. The smaller FX was built alongside the Ford-O-Matic at the Fairfax Transmission Plant and was put in midrange Ford and Mercury models. Because the original Ford-O-Matic started in second rather than first, it was marketed as a two-speed after the new three-speed transmissions were introduced. Production continued until it was replaced by the C4 in 1964 and application was for smaller Ford and Mercury vehicles....

Fordomatic two-speed[edit]

The Fordomatic two-speed transmission was introduced in 1959. A simplified version of the Cruise-O-Matic, it combined a torque connector and a compound planetary gear set. A front unit (multiple-disc) clutch provided high gear, a front band on the clutch drum provided low gear, and a band on the rear unit internal gear drum provided reverse. This transmission was offered on Ford, Fairlane, Mercury, Edsel, Falcon, Comet and Meteor cars with differences in the torque converter, valve bodies and clutch plates to accommodate differing engine torques.


Ravigneaux planet carrier from a Ford FMX, with a dinner fork to show scale

In 1966, Ford introduced the C6 automatic, which left them with three heavy-duty automatic transmissions and crowded conditions at Livonia Transmission plant. Ford decided to combine the best attributes of the MX and FX transmissions and ended up with an improved version of the "X" called FMX. This transmission used the stronger MX-type rotating parts in the smaller FX style case. This cut down on both weight and the number of transmission components Ford needed to make. This transmission was manufactured at the Fairfax Transmission Plant, freeing up capacity at Livonia for the new C6. The FMX was manufactured from 1968 to 1979, when the Fairfax Transmission plant was closed.

Although the FMX was phased out in the United States in 1979 in favor of Ford's then-revolutionary Automatic OverDrive (AOD) transmission, the FMX was sold for another four years for use in V8 Ford Falcons built in Australia. The FMX ceased production when Ford Australia phased out the V8 engine in 1983.

Gear ratios[edit]

  • First: 2.40:1
  • Second: 1.47:1
  • Third: 1.00:1
  • Reverse: 2.00:1


In 1962, Ford began working on a new type of automatic transmission to emphasize fuel economy and driveability. The new transmission was built around the Ravigneaux planetary of the "X" transmissions. Where many transmissions had a fourth gear added as an afterthought, Ford's new transmission was designed with a fourth gear already integrated into the gearset. Because it was based on the X transmissions, its gear ratios from 1-3 were the same, with the fourth being .67:1. The transmission featured a split-torque application for third gear, as well as a lockup in the torque converter. The project was shelved with a design that initially lacked a dampener in the torque converter, but after the project was revisited, a dampener ultimately made its way into the final design before Job 1.[clarification needed] The XT-LOD was initially abandoned in 1966, but revisited in 1974 as a result of rising gas prices. The transmission was introduced when Ford downsized its full size line for 1979. Initially called XT-LOD (Extension Lock-Up Overdrive), its name was changed when revisited in 1974 to FIOD (Ford Integrated Overdrive) and then to its final name in 1979, the Ford AOD transmission.[5]

See also[edit]


  1. ^
  2. ^ a b Flory, Jr., J. "Kelly" (2008). American Cars, 1946-1959 Every Model Every Year. McFarland & Company, Inc., Publishers. ISBN 978-0-7864-3229-5. 
  3. ^ "A Brief History of Ford Automatic Transmissions". Baumann Engineering. Retrieved 2011-11-20. 
  4. ^
  5. ^ "Ford Automatic Transmissions: An Anecdotal History" (PDF). ATEO Communicators. Retrieved 2012-01-02.