Dynaflow transmission, while Pontiacs used Chevrolet's Powerglide, both two-speed torque-converter units. Non-GM makes that bought Hydra-Matics from the corporation, including Ford Motor Co.'s Lincoln division and independent automakers Hudson, Kaiser, and Nash ended up looking for other sources of automatic transmissions as well, with Lincoln using the Borg-Warner-designed Ford-O-Matic transmission, while other automakers also switched to automatics from Borg-Warner during the downtime. About nine weeks after the Livonia fire, GM opened up a new source for Hydra-Matic production at Willow Run, Michigan. By the time the 1954 models debuted in late 1953, Hydra-Matic production had returned to normal levels and all '54 model Cadillacs, Oldsmobiles, and Pontiacs with automatic transmissions were once again equipped with Hydra-Matics. Evolving by the pressure of industrial competition from other manufacturers such as Studebaker's three-speed lock-up torque converter co-designed by Detroit Gear (a division of Borg-Warner), named DG 200/250, and Packard's dual-range two-speed lock-up torque converter coupled Ultramatic, GM's Hydra-Matic underwent several revisions through 1955, before being gradually replaced by the substantially redesigned Controlled-Coupling HydraMatic (also called Jetaway, by Oldsmobile, and StratoFlight, and later Super Hydra-Matic, by Pontiac, or 315 HydraMatic, by Cadillac, or Dual-coupling Hydra-Matic) in 1956. The Controlled-Coupling Hydra-Matic incorporated a secondary fluid coupling and a pair of sprag clutch in place of the former friction clutch and brake bands, shifting in part by alternately draining and filling the secondary coupling. It was a later version of GM's "dual-range Hydra-Matic", first introduced in some 1952 models. The dual range feature allowed the driver to hold the transmission in third gear until the maximum allowable upshift points, for improved performance in traffic or in mountain driving. The new, dual coupling transmission also incorporated a separate park position, falling in line with other automatic transmissions of the day. Controlled-Coupling Hydra-Matic was substantially smoother than the original Hydra-Matic, but also more complex and expensive to produce, just as efficient as the original HydraMatic because all HydraMatic transmissions, including Roto Hydra-Matic and Tempest Torque, use the split-torque design. In 1961, The model 375 Roto Hydramatic was produced. The Roto is a four range three speed unit. The Roto eliminated the front fluid coupling that was used in the Controlled coupling Hydramatic and the connection between the engine and transmission was made by using the small fluid coupling that is used also to control the front planetary gear set' (in which the "dump and fill" shifting principle was