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The Ford PowerShift is a six- or seven-speed dual-clutch automatic transmission, produced by the Ford Motor Company. [1] The older Ford PowerShift gearboxes were built by Getrag Ford Transmissions, a joint-venture with Getrag, however it is unknown who exactly makes the newer 7-speed models. [2] PowerShift improves fuel efficiency by as much as 10 percent when compared to a conventional automatic transmission. [1]
The operation of a dual-clutch transmission is analogous to two traditional manual transmissions, each with its own clutch, operating in parallel and alternating shifts. The Ford unit is a six-speed with one clutch acting on reverse, first, third, and fifth gears, and the other used for second, fourth, sixth gears. As the first gear is engaged, the 2-4-6 clutch is disengaged and the second gear cogs are engaged. At the appropriate time, the R-1-3-5 clutch is disengaged and the 2-4-6 clutch is engaged. While in second gear, the other side shifts from first to third. The process is repeated with none of the efficiency loss normally associated with torque converters and, in theory, provides quick smooth shifts.
The older PowerShift gearboxes were developed jointly by Ford, Getrag, and LuK and were first introduced in Europe.
Lower torque versions of the PowerShift transmission, including the 6DCT250 DPS6 version used in the Ford Fiesta and Ford Focus, used dry clutches and electric motor/solenoid actuation. [2]
Newer PowerShift transmissions are still manufactured by Getrag and can be found on Ford Fiesta and Puma models starting with MY2020, these are known as 7DCT300 (wet clutch).
Newer vehicles like Fiesta and Puma use the newer 7-speed PowerShift, while others have reverted to a torque-converter automatic.
P3 Volvo models using the EcoBoost engine in 1.6T derivatives are equipped with the 6-speed PowerShift, some older P3 platform cars feature the 6-speed PowerShift in 2.0T derivatives (Badged T3 (1.6T), T4 (1.6T), and 2.0T)
By model year 2015, all Volvo cars had stopped using EcoBoost engines and the only automatic transmission options were from Aisin.
The use of cheaper, lighter and simpler dry clutch packs in lower-end models of the transmission ultimately led to the demise of the PowerShift name.
The gearboxes with dry clutch packs were used in the Fiesta, Focus and EcoSport. Dry clutches are designed to be used in manual transmissions, and are known to have very peculiar engagement properties, unlike wet (oil-bathed) clutches which are much smoother in operation, and have a higher tolerance for slipping the clutches as they have better heat dissipation. This all makes wet clutches better suited for use in DCTs, and thus Ford experienced problems with models of the transmission which used dry clutch packs.
Ford has faced class-action lawsuits and fraud investigations in the United States, [4] Australia [5] and Canada [6] over the PowerShift gearbox as being defective and potentially dangerous in the Ford Focus, Ford Fiesta and Ford EcoSport. The lawsuits allege that vehicles equipped with the PowerShift gearbox "continue to experience the transmission defect, including, but not limited to, bucking, kicking, jerking, harsh engagement, and delayed acceleration and lurching." U.S. courts tentatively approved a settlement of the U.S. lawsuit on April 25, 2017. [7]
Ford has claimed that the defects were caused by either a faulty throwout bearing or input shaft and rear main seals that leak fluid onto the clutch causing it to slip even while supposedly fully engaged. Ford has released fixes of the seals and updated clutch kits. There were also issues with the transmission control module such as faulty connector pins, shifter motors failing, and a poorly connected main ground wire due to paint on threads or an incorrect bolt being used during assembly. These transmissions were still installed into Focus and Fiesta until Ford introduced newer models to replace them.
However, subsequent journalistic investigations conducted after the Focus and Fiesta models were succeeded, has revealed that Ford engineers and executives were aware of the problems before and after the release of it, with developmental engineers even stating in company e-mails that there was "no driveable calibration" of the transmission, and with pre-production test engineers having to pull over out of traffic due to the transmission shifting into neutral. These were mainly caused by the clutch pack overheating, and the control module instructing clutches to disengage in order to prevent further damage; however faulty control modules may also exhibit such behaviour. However, Ford has repeatedly denied systemic problems even to their own dealerships, instead directing them to replace the transmission over and over even though it was never truly fixed. [8]
Ford Thailand agreed to buy back about 200 Ford Fiesta and Focus models with faulty PowerShift transmissions. [9] [ unreliable source ] Ford Brazil extended the warranty of the transmission to 10 years or 240.000 km. Ford USA extended the warranty of the transmission to 7 years or 100,000 miles depending on the model year of the vehicle. Ford Australia has had a $AU10,000,000 fine imposed on it by the Australian Federal Court for unconscionable conduct relating to the transmission problems and poor handling of customer complaints [10] Ford is now[ when? ] under a US Department of Justice fraud inquiry to determine if the company was aware of a defect that it knew to be irreparable, or if it may have misled customers and safety regulators. [11]
A clutch is a mechanical device that allows the output shaft to be disconnected from the rotating input shaft. The clutch's input shaft is typically attached to a motor, while the clutch's output shaft is connected to the mechanism that does the work.
An automatic transmission is a multi-speed transmission used in motor vehicles that does not require any input from the driver to change forward gears under normal driving conditions. Vehicles with internal combustion engines, unlike electric vehicles, require the engine to operate in a narrow range of rates of rotation, requiring a gearbox, operated manually or automatically, to drive the wheels over a wide range of speeds.
Overdrive is the operation of an automobile cruising at sustained speed with reduced engine revolutions per minute (RPM), leading to better fuel consumption, lower noise, and lower wear. The term is ambiguous. The most fundamental meaning is that of an overall gear ratio between engine and wheels, such that the car is over-geared, and cannot reach its potential top speed, i.e. the car could travel faster if it were in a lower gear, with the engine turning at higher RPM.
A transmission is a mechanical device which uses gears to change the speed or direction of rotation in a machine. Many transmissions have multiple gear ratios, but there are also transmissions that use a single fixed gear ratio.
A manual transmission (MT), also known as manual gearbox, standard transmission, or stick shift, is a multi-speed motor vehicle transmission system, where gear changes require the driver to manually select the gears by operating a gear stick and clutch.
A semi-automatic transmission is a multiple-speed transmission where part of its operation is automated, but the driver's input is still required to launch the vehicle from a standstill and to manually change gears. Semi-automatic transmissions were almost exclusively used in motorcycles and are based on conventional manual transmissions or sequential manual transmissions, but use an automatic clutch system. But some semi-automatic transmissions have also been based on standard hydraulic automatic transmissions with torque converters and planetary gearsets.
Getrag, stylized as GETRAG, was a major supplier of transmission systems for passenger cars and commercial vehicles. The company was founded on 1 May 1935, in Ludwigsburg, Germany, by Hermann Hagenmeyer; as the Getriebe und Zahnradfabrik Hermann Hagenmeyer GmbH & Cie KG.
R.T. Quaife Engineering, Ltd. is a British manufacturer of automotive drivetrain products. It designs and manufactures motorsport and performance orientated gearboxes, gearkits, differentials, steering racks and axle kits, along with many other associated drivetrain products.
A direct-shift gearbox is an electronically controlled, dual-clutch, multiple-shaft, automatic gearbox, in either a transaxle or traditional transmission layout, with automated clutch operation, and with fully-automatic or semi-manual gear selection. The first dual-clutch transmissions were derived from Porsche in-house development for the Porsche 962 in the 1980s.
A preselector gearbox is a type of manual transmission mostly used on passenger cars and racing cars in the 1930s, in buses from 1940-1960 and in armoured vehicles from the 1930s to the 1970s. The defining characteristic of a preselector gearbox is that the gear shift lever allowed the driver to "pre-select" the next gear, usually with the transmission remaining in the current gear until the driver pressed the "gear change pedal" at the desired time.
7G-Tronic is Mercedes-Benz's trademark name for its seven-speed automatic transmission, starting off with the W7A 700 and W7A 400 as core models.
A transmission control unit (TCU), also known as a transmission control module (TCM), or a gearbox control unit (GCU), is a type of automotive ECU that is used to control electronic automatic transmissions. Similar systems are used in conjunction with various semi-automatic transmissions, purely for clutch automation and actuation. A TCU in a modern automatic transmission generally uses sensors from the vehicle, as well as data provided by the engine control unit (ECU), to calculate how and when to change gears in the vehicle for optimum performance, fuel economy and shift quality.
Twin Clutch SST is the brand name of a six-speed dual-clutch automatic transmission, developed by Getrag for Mitsubishi Motors. The system was first incorporated in the 2008 Lancer Evolution X, and was designed to be a more performance-oriented system than that developed by rival manufacturers, with shorter gear ratios optimized for acceleration.
The Ford Focus (third generation), also known as the Focus Mk III, (Code name: C346) debuted at the 2010 North American International Auto Show as a 2012 model. The cars shown were a 4-door sedan and 5-door hatchback, also debuting a new 2.0-litre direct injection I4 engine. A 5-door estate (wagon) was previewed at the Geneva Motor Show a month later.
A dual-clutch transmission (DCT) is a type of multi-speed vehicle transmission system, that uses two separate clutches for odd and even gear sets. The design is often similar to two separate manual transmissions with their respective clutches contained within one housing, and working as one unit. In car and truck applications, the DCT functions as an automatic transmission, requiring no driver input to change gears.
9G-Tronic is Mercedes-Benz's trademark name for its nine-speed automatic transmission, starting off with the W9A 700 as core model.
The Volvo I-Shift is an automated manual transmission developed by Volvo subsidiary Volvo Powertrain AB for Volvo Trucks and Volvo Buses, with 12 forward gears and 4 reverse gears. It became available for trucks in 2001 and later buses in 2004.
The Ford Fiesta Mk6/Mark VI is the sixth generation of the Ford Fiesta supermini. The sixth generation Fiesta was shown in a concept car form as the Ford Verve at the Frankfurt Motor Show in September 2007, with introductions in Europe, the Americas, Asia, Australasia, and Africa. Developed under the project code B299 and B409, the model uses the Ford global B-car platform newly developed for the model.