TorqueFlite

TorqueFlite

Manufacturer	Chrysler Corporation
Production	1956–
Predecessor	PowerFlite
Class	3- or 4-speed automatic

TorqueFlite (also seen as Torqueflite) is the trademarked name of Chrysler Corporation's automatic transmissions, starting with the three-speed unit introduced late in the 1956 model year as a successor to Chrysler's two-speed PowerFlite. In the 1990s, the TorqueFlite name was dropped in favor of alphanumeric designations.

Torqueflite 42RE

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 [1] and Bristol [2], 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).

Nomenclature

Torqueflite transmissions and transaxles made through 1991 were assigned arbitrary designations consisting of the letter "A" followed by three digits. 1992 and later units have four-character designations in which the first through fourth characters indicate, respectively, the number of forward speeds, torque capacity, drive type or transaxle orientation, and control system:

Forward speeds	Torque capacity	Drive type	Control
3 or 4	1 (low) to 9 (high)	R (Rear wheel) T (Transverse) A (All-wheel)	H (Hydromechanical) E (Electronic)

Technology

Torqueflites use a torque converter and the Simpson Gearset, two identical planetary gearsets sharing a common sun gear. Chrysler Corporation licensed this gearset from Simpson in 1955^{[citation needed]}.

Rear-wheel drive transmissions

A488

The original TorqueFlite was designated A488, with a cast iron case and no parking pawl.

A500

The A500, later 40RH/42RH (hydraulic) and 40RE/42RE/44RE (electronic), was an A904 derivative used in trucks and vans. Introduced in the 1989 model year on a limited basis, it was the first light-duty Chrysler four-speed automatic and was placed behind the 3.9 L and 5.2 L engines for light-duty purposes. A tailshaft overdrive unit was bolted to the rear of the case to provide a total of four forward speeds, and was replaced by the 42RLE in 2004. This transmission is known for its whistle upon acceleration and deceleration.

Gear ratios:

1	2	3	4	R
2.74	1.54	1.00	0.69	2.21

Applications:

• 1989-2001 Dodge Ram pickup 150/1500 V6/V8(2WD)
• 1989-2003 Dodge Ram Van B150/B250 V6/V8
• 1989-2003 Dodge Dakota
• 1993-2004 Jeep Grand Cherokee I6
• 1996-1998 Jeep Grand Cherokee 5.2 V8

A518

The A518, later 46RH (hydraulic controlled governor pressure) and 46RE (electronic controlled governor pressure), is an A727 derivative with overdrive. Starting in the early 1990s, it was used in trucks and vans. The overdrive fourth gear ratio is 0.69:1.

Gear ratios:

1	2	3	4	R
2.45	1.45	1.00	0.69	2.35

Applications:

• Dodge Ram pickup and vans 1500/2500/3500 V8 engines (DGT)
• Dodge Dakota R/T (1998-2003)
• Jeep Grand Cherokee 1998 5.9L
• Jeep Grand Cherokee 1993-1995 5.2 V8

A618

The A618, later 47RH (hydraulic controlled governor pressure) and 47RE (electronic controlled governor pressure), is a heavier-duty version of A518. It was used in trucks and vans starting in the mid-1990s. While currently used with some internal changes when coupled to the 5.9 L Cummins Turbo-Diesel and the 8.0 L V-10 applications, it's still a 727 with overdrive and stronger internal parts. It has an input torque rating of 450 lb·ft (610 N·m).

Gear ratios:

1	2	3	4	R
2.45	1.45	1.00	0.69	2.21

Applications:

• Dodge Ram pickups 2500/3500 ISB Diesel and iron V-10 (DGP)
• Dodge Ram SRT-10 (DGP)f

A727

The A488 was replaced in 1962 with the A727 (later 36RH and 37RH), with an aluminum case to reduce weight by about 60 lb (27 kg). The A727 incorporated a parking pawl and various internal improvements, and used a 10.75 in (27.3 cm) or 11.75 in (29.8 cm) torque converter. The heavier-duty A727 Torqueflites became — and remain — popular for drag racing and monster truck applications because of their controllability and strength.

• 1962-1978 361 , 383 , 400 B-Motor V8
• 1962-1978 413 , 426 wedge , 440 RB-V8
• 1964-1965 426 Hemi Super Stock
• 1966-1971 426 "Street" Hemi
• 1962-1966 318 "A" "Poly" V8
• 1968-1973 340
• 1971-1978 360
• H.D. 225 Slant Six (Police , Taxi , Light-Duty Pickups , "A" Van , "B" Van )

was known as "A-727-RG" ( Raised-deck "G" Motor )

• 1972-c.1978 AMC 304 , 360 , 401 V8 "Torque-Command 8"

A904

For standard-duty applications in smaller and lighter vehicles with 6-cylinder or small V8 engines, the compact A904 (later 30RH) was introduced in 1960. This transmission used a 10.75 in (27.3 cm) torque converter. There was also a smaller version of this transmission used in the Dodge Colt/Plymouth Champ cars made by Mitsubishi in Japan. This smaller transmission used a 10 in (25 cm) torque converter.

Uses:

• 1960-1976 170 , 198 , 225 Slant Six
• 1964-1969 273 LA-V8
• 1967-1978 318 LA-V8
• 1975-1978 360 2Bbl LA-V8
• 1972-c.1978 AMC I-6 "Torque-Command 6"

A998

The A998 (later, 31RH) was a medium-duty, wide-ratio version of the small-frame A904 transmission for use with medium-power V8 engines and the 3.9 L V6 engine.

The 998 was equipped with four direct friction plates.

These automatics had lower first and second gear ratios to allow the lower-powered engines to provide better acceleration without sacrificing highway fuel economy.

A999

The A999 (later 32RH) was a heavier-duty, wide-ratio version of the small-frame A904 transmission for use with medium-power V8 engines and the 3.9 L V6 engine.

The 999 was equipped with five direct friction plates.

These automatics had lower first and second gear ratios to allow the lower-powered engines to provide better acceleration without sacrificing highway fuel economy.

Uses:

• Jeep Wrangler TJ's with the 4.0 straight 6

30RH

A renamed light-duty A904.

31RH

A renamed medium-duty A998.

32RH

A renamed heavier medium-duty A999.

40RH

A renamed light-duty A500. A904 with overdrive and hydraulic control.

42RH

A renamed medium-duty A500. A998 with overdrive and hydraulic control.

44RE

A renamed heavy-duty A500. A999 with overdrive and electrical control.

46RH

A renamed A518. A727 with overdrive and hydraulic control.

Applications:

• 1994-1995 Dodge Ram 2500/3500 V8
• 1993-1995 (Jeep Grand Cherokee 5.2)
• 1995 Dodge Dakota 5.2l magnum v-8
• 1995 Dodge Ram Van 2500 5.2L Magnum V8

46RE

A renamed second-generation A518. A727 with overdrive and electrical control.

Applications:

• 1996 Dodge Dakota V8 (Also 98-03 Dakota 5.9L R/T)
• 1996-2002 Dodge Ram 1500/2500/3500 V8
• 1998-2000 Dodge Durango 5.9L V8 (4WD or 2WD)
• 1998 Jeep Grand Cherokee 5.9L V8 (4WD)

47RH

A renamed A618 and hydraulic control.

Applications:

• 1994-1995 Dodge Ram 2500/3500 Diesel/V10

47RE

A renamed second-generation A618. A heavy-duty A727 with overdrive and electrical control.

Applications:

• 1996-2002 Dodge Ram 2500/3500 Diesel/V10

48RE

The 48RE is an electronically-governed, fourtim-speed heavy-duty overdrive automatic transmission, stronger than its predecessor, the 47-series.

Gear ratios:

1	2	3	4	R
2.45	1.45	1.00	0.69	2.21

Applications:

• 2003-2004 Dodge Ram 2500/3500 ISB Diesel
• 2003-2004 Dodge Ram 2500/3500 HO ISB Diesel
• 2004-2007 Dodge Ram 2500/3500 600/610 Diesel
• 2004-2006 Dodge Ram SRT-10

Front-wheel drive transaxles

The A404, A413, A470, and A670 are front wheel drive transaxle derivatives of the A904 Torqueflite.

In the late 1970s, Chrysler designed the A404 TorqueFlite three-speed automatic transaxle for its front wheel drive Dodge Omni and Plymouth Horizon subcompact cars. This transaxle would be upgraded in the 1980s into the A413 and A670 units, which were progressively heavier-duty, for Chrysler's K-cars and their derivatives, including the minivans. The four-speed Ultradrive electronic four-speed automatic transaxle would eventually replace it, but the three-speed lasted for more than a decade after the 1989 debut of the four-speed unit.

A404

The light-duty A404 was used with the smallest straight-4 engines from Chrysler, commonly the 1.7 L Volkswagen unit.

A413 or 31TH

The A404 was strengthened to become the A413 (later 31TH) in 1981. This was used with Chrysler's 2.2 and 2.5 L K-car engines. It was available both with and without a lockup torque converter. This transmission was also used in the Dodge Neon from 1995-2001. The A413 is broadly similar in concept to Ford's ATX three-speed unit.

A415

The A415 was developed for the 1.6 L Simca 1100 engine, but was not released for series production.

A470

The A470 was a strengthened version of the transaxle used with the 2.6 L Mitsubishi Astron engine in the K-cars from 1981-1985 and minivans from 1984 through 1987.

A670

The highest-specification three-speed transaxle was the A670. It was used with the 3.0 L Mitsubishi V6 engine in Chrysler's cars and minivans from 1987-2000.

Gear ratios:

1	2	3	R	Final
2.69	1.55	1.00	2.10	3.02

• List of Chrysler transmissions
• AMC/Jeep Transmissions
• Pan Shapes and Naming

• "TorqueFlite Transmission". Allpar.com. http://www.allpar.com/mopar/torqueflite.html. Retrieved February 22, 2006. 
• "Mopar Trans ID Guide". Car Craft. http://www.carcraft.com/newlook/crc_act/116_0302_trans/.