TorqueFlite - History

History

The first Torqueflites provided three speeds forward plus reverse. Gear ratios were 2.45:1 in first, 1.45 in second, and 1.00 in third. The transmission was controlled by a series of pushbuttons located on the vehicle's dashboard. The buttons were generally at the extreme driver's side end of the dash, i.e., the left in left-hand drive vehicles, and the right in right-hand drive ones. However, this was not always the case; the 1962 Dodge Phoenix, a right-hand drive export model sold in Australia and South Africa, used the U.S. 1962 Plymouth Valiant instrument cluster assembly, into the left end of which were integrated the transmission pushbuttons. Button arrangement varied by vehicle model and year; sequence was Reverse, Neutral, Drive, Second, and First, from top to bottom with vertically-arrayed buttons, from left to right with horizontally-arrayed buttons, and clockwise starting at upper left with clustered buttons.

A parking lock was not provided until the advent of the aluminum-case Torqueflites in 1960 (standard-duty A-904) and 1962 (heavy-duty A-727), at which point a lever was added adjacent to the pushbuttons: Throwing the lever to the "Park" position placed the car into Neutral and engaged a lock pawl on the transmission's output shaft. Throwing the park lever out of "Park" position unlocked the shift buttons so that a driving range could be selected. The buttons were replaced by conventional steering column- or floor-mounted shift levers in all automatic Chrysler-built vehicles for the 1965 model year, though floor levers were available in certain sporty 1964 models.

Like a vehicle with a General Motors Hydramatic, a vehicle with a Torqueflite transmission starts out in first gear when the Drive or Second position is selected. This is in contrast to vehicles with several automatics from Ford and Borg-Warner, which start out in second rather than first if the Second position is selected.

1962 brought the addition of a canister-style fluid filter installed in the cooler line. For 1964, the canister filter was eliminated, and the transmission's internal intake screen was replaced by an efficient Dacron filter. Fluid life starting in 1964 was extended from 12,000 mi (19,000 km) to 50,000 mi (80,000 km), providing justification for the deletion of the drain plug from the oil pan.

For 1966, the twin-cable shift and park control mechanism (a holdover from the push-button operation) was replaced by a solid shift control linkage consisting of a series of pushrods, rotating rods and levers. The rear pump was eliminated, which simplified and cost-reduced the transmission but rendered push-starting impossible; Chrysler engineers reasoned that improved electrical and fuel systems reduced the need to push-start vehicles, and safety concerns weighed against doing so. The gated shift quadrants also permitted the deletion of the reverse safety blocker valve which, in TorqueFlites made through 1965, had shifted the transmission harmlessly into Neutral if the Reverse position were selected with the vehicle moving forward above approximately 3 mph (4.8 km/h).

In 1968, part-throttle downshift functionality was added to A-904 transmissions used with 6-cylinder engines. This feature permitted the transmission to shift from third to second gear in response to moderate accelerator pressure. Previously, an automatic 3-2 downshift occurred only if the driver pushed the accelerator to the floor. This change was made to maintain acceptable in-town performance with taller final-drive ratios in the rear axle — 2.76:1 rear axle gears were being furnished in applications previously equipped with 2.93:1 or 3.23:1 gearsets. Part-throttle downshift functionality was extended to V8 A-904s in 1969, and to most A-727 transmissions in 1970 to 1971.

In 1978, most Torqueflite transmissions gained a lockup torque converter clutch to mechanically connect the converter's impeller and turbine, eliminating slip for better highway fuel economy. This addition required the removal of the torque converter drain plug.

For 1980, a wide-ratio gearset was released for the A904, A998 and A999, with 2.74:1 in first, 1.54 in second, and 1.00 in third.

Torqueflite was an available option or standard equipment, depending on model and year, on all Chrysler products: Plymouth, Dodge, DeSoto, Chrysler and Imperial. It was also used by American Motors beginning in 1972, where it was named TorqueCommand, as well as by Jeep, International Harvester, Maserati Quattroporte, Monteverdi and Bristol, as well as several brands of light and medium-duty trucks and panel vans. When installed in Dodge trucks and vans, the transmission was marketed as LoadFlite.

In the 1990s, the transmissions were renamed, however the original Torqueflite design remained the basis of many Chrysler designed (and built) transmissions thru 2007 (and FWD transaxles thru 2000).

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