The first automatic TorqueFlite transmission was the A-488 which debuted in the 1956 Imperial. It was sealed in a case made of iron, and had both a front and rear pump, the latter allowing push-starts. Because the transmission used push-buttons to shift, it was shifted into neutral by a reverse blocker valve in case drivers accidentally pushed reverse while moving forward.
The Famous 727
According to professionals, the toughest TorqueFlite transmission was the A-727. It is the one most used by exotic automobile manufacturers. The A-727 replaced the A-488 in 1962 and was used in every V-8 car and heavy-duty vehicles, including trucks, until the 1964 model year. The A-727 weighed 60 pounds less than its predecessor by 60 pounds by using an aluminum case.
The first variant of the A-488 was the A-904, the TorqueFlite 6, used in some of the 1960 cars. Scaled down with an aluminum case, it had two pumps, until after the 1965 model year.
The A-727 used a lock to park, activated by a lever on some 1962-64 models, or by putting the shift into “park” from the 1965s on. Not all of the early A-727s had a parking lock, but it would eventually become standard equipment.
Early A-727s came with dual pumps, but in the 1966 trucks and cars, the rear pump was dropped, probably to lower costs. The A-727 was very different from the A-488s, as they shared no parts.
According to an earlier issue of a popular car magazine, they state Chrysler TorqueFlite is one of the most trouble-free transmissions in the world. Even if compared to the Rolls-Royce and Mercedes-Benz.
The TorqueFlite automatic transmission, three-speed, from the 1950s to the 90s, was Chrysler’s go-to transmission. The basic design remains essential in current transmissions for trucks.
The TorqueFlite was adopted by luxury automobile makers such as Maserati, Aston Martin, Bristol, Facel Vega, Monteverdi, and Jensen. It was also used in the domestic rival AMC and in commercial vehicle makers including Land Rover, International Harvester, Matbro, Karrier, Iveco, Mitsubishi, Boss Motor, Sirmac, Boss Motor, and Stonefield.
Beginning with the 1964 model year vehicles, a sturdier version of the A-904 was produced to work with the company’s lower-performance V8 engines. AMC used both the A-727 and the A-904, calling them Torque-Command. Various components of the transmission could change depending on the vehicle and year.
Pushing Innovation
At the end of 1964, The company moved from pushbuttons to a single-rod making it more difficult to go into reverse while moving forward accidentally. They dropped the reverse blocker as well.
For the 1971 model years, a partial-throttle kickdown was added to avoid having to floor the gas pedal to downshift. This was a major advantage for drivers, as the powertrain reacted quickly to sudden demands for more, but not full-throttle, power.
A big change came with the 1978 Plymouth Horizon and Dodge Omni. Chrysler packaged the TorqueFlite automatic into a front-wheel-drive. This basic transmission made it into the 21st century, used in the Neon series, after powering countless cars and minivans.
Many 1978 rear drive cars had a new addition as well. Lockup torque converters used a mechanical lock instead of the typical fluid interface in the torque converter. The TorqueFlite adopted variable line pressure for reverse, which lowered the pressure which helped to keep the seals from leaking or wearing out. A regulator value was added for pressure when required.
Beginning in 1980, a gearset was created for both the 998 and 999 transmissions. It was noisier and less durable because of its welded-steel cage than those with the original machined aluminum cage. But the wider gear spread helped to compensate for “economy” axle ratios. It was made standard in 1981.
In 1986, the front wheel drive version of the TorqueFlite was modified. All of the front transaxles on engines, non-turbo, except for the 2.5L engine on the Caravan and Voyager, had lockup torque converters that were electronically controlled. The rear-drive version of the TorqueFlite transmission had a non-electric lockup at the time.
More Advancements
It is felt by some automotive professionals that the rear wheel drive TorqueFlite design continued past the period of time when transmissions were so called. In 1989 and 1991 overdrives were added which resulted in the A-500, formerly the A-904. And the A-518, formerly the A-727. The engine computer had an electric overdrive unit in the extension housing. The new automatics were only used in Jeeps and in pickups. In the meantime, cars got more complex and so did the more troublesome units.
In 1994, new names were adopted. The old A-904 plus an overdrive gear became the 42RE. The 42RE was used in:
- Dodge Dakota 1989-2003
- Dodge Durango 1998-2000
- Dodge Ram pickup 1989-2001
- Dodge Ram Van 1989-2003
- Jeep Grand Cherokee 1993-2004
- Jeep Grand Cherokee 1996-1998
The 42RE was first used in a Jeep Cherokee in late 1993. It is a four-speed, automatic overdrive, electronically controlled transmission with a hydraulic control. It is believed by those in the know, that the 42RE is a reliable transmission and is good for many miles. Keep fluid levels consistent and cool, and do not use O/D when towing.
The 42RE transmission weighs around 125 to 150 lbs. and could weigh an additional 125 pounds if there is a transfer case attached to it.
If you find you need to replace your 42RE, you can have it rebuilt, remanufactured, or purchase a used one. The best option of these three is the remanufactured as it is “literally” rebuilt from the core. The rebuilt transmission will replace only the components that are defective. And if you decide to purchase a used transmission from a private party, you never know what you are getting. There is a full list of vehicles that use the 42RE transmission in the drivetrain at https://reman-transmission.com.
Final thoughts on the TorqueFlite
Bert Cartwright, the designer of the TorqueFlite transmission is said to be the best transmission designer in the world and proved that with the successors of the 42RE like the 44RE, 46RE, 47RE, and 48RE. This article on the Jeep Grand Cherokee has a great section discussing the 44RE transmission. The TorqueFlite transmission was based on the Simpson gear set, which was licensed to Ford in 1953 and to Chrysler in 1955. It used two identical gears with a common “sun” gear. Stronger or larger gears could improve your power capability.
Introduced in 1956 by Chrysler and Imperial, the TorqueFlite was simply the best automatic transmission over built. It was economical, efficient, quiet, dependable, and simple. The transmission gave Chrysler cars a distinct performance advantage over others.
