Editing Semi-automatic transmission (section)

== Usage in passenger cars ==
=== 1900s–1920s ===
[[File:1913-1923 Amédée BOLLÉE Fils Type F Berline crop.jpg|thumb|Bollée Type F Torpedo with gear shift ring located inside the steering wheel]]

In 1901, [[Amédée Bollée]] developed a method of shifting gears that did not require the use of a clutch and was activated by a ring mounted within the steering wheel.<ref name="lemans-paddle">{{cite web |title=The history of the 'paddle shift' |url= https://www.lemans.org/en/news/the-history-of-the-paddle-shift/2922 |website=lemans.org |date=21 February 2011 |access-date=2020-02-16}}</ref> One car using this system was the 1912 [[Léon Bollée Automobiles|Bollée]] Type F Torpedo.

=== 1930s–1940s ===
Prior to the arrival of the first mass-produced hydraulic automatic transmission (the [[General Motors]] [[Hydramatic|Hydra-Matic]]) in 1940, several American manufacturers offered various devices to reduce the amount of clutch or shifting input required.<ref>{{cite web|url= https://www.caranddriver.com/research/a31862769/how-does-an-automatic-transmission-work/ |title = How Does an Automatic Transmission Work?|date = 13 April 2020}}</ref> These devices were intended to reduce the difficulty of operating the [[Non-synchronous transmission|unsynchronised manual transmissions]], or "crash gearboxes", that were commonly used, especially in stop-start driving.

An early step towards automated transmissions was the 1933–1935 [[REO Motor Car Company|REO]] Self-Shifter,<ref name="hagerty.com">{{cite web |title=6 of the worst automatic transmissions ever |url= https://www.hagerty.com/media/maintenance-and-tech/6-of-the-worst-automatic-transmissions-ever/ |website=hagerty.com |access-date=9 August 2020 |date=8 August 2019}}</ref><ref>{{cite web|url= https://www.autoindustriya.com/features/making-automatic-sense.html |title = Making Automatic Sense – Feature Stories|date = 29 September 2010}}</ref><ref>{{cite web|url= https://www.caranddriver.com/research/a31884931/what-is-an-automatic-car/ |title = What is an Automatic Car?|date = 13 April 2020}}</ref><ref>{{cite web|url=https://www.caranddriver.com/research/a31862769/how-does-an-automatic-transmission-work/ |title = How Does an Automatic Transmission Work?|date = 13 April 2020}}</ref> which automatically shifted between two forward gears in the "forward" mode (or between two shorter gear ratios in the "emergency low" mode). Standing starts required the driver to use the clutch pedal. The Self-Shifter first appeared in May 1933 and was offered as standard on the Royale and as an option on the Flying Cloud S-4.<ref>{{cite web|url= http://auto.howstuffworks.com/reo-cars1.htm |title=How Reo Cars Work|date=15 June 2007|access-date=24 October 2017}}</ref>

In 1937, the four-speed [[Oldsmobile]] Automatic Safety Transmission was introduced on the [[Oldsmobile Six]] and Oldsmobile Eight models.<ref name="hagerty.com"/> It used a planetary gearset with a clutch pedal for starting from a standstill and switching between the "low" and "high" ranges.<ref>{{cite web |title=The Oldsmobile automatic safety transmission operated by the short lever shown on the steering column. |url= https://digitalcollections.nypl.org/items/510d47db-bb52-a3d9-e040-e00a18064a99 |website=nypl.org |access-date=9 August 2020 |language=en}}</ref><ref>{{cite web |title=No clutch to press! No gears to shift! |url= https://www.autonews.com/article/19970818/ANA/708180702/no-clutch-to-press-no-gears-to-shift |website=autonews.com |access-date=9 August 2020 |language=en |date=18 August 1997}}</ref><ref>{{cite web |title=How Oldsmobile Cars Work |url=https://auto.howstuffworks.com/oldsmobile-cars1.htm |website=howstuffworks.com |access-date=9 August 2020 |language=en |date=20 June 2007 |archive-date=20 September 2020 |archive-url=https://web.archive.org/web/20200920073229/https://auto.howstuffworks.com/oldsmobile-cars1.htm |url-status=dead }}</ref> The Automatic Safety Transmission was replaced by the fully-automatic Hydra-Matic for the 1940 model year.<ref>{{cite web|url= https://quality-coaches.com/transmission-repair/the-evolution-of-the-auto-transmission/|title=The Evolution of the Auto Transmission |website=quality-coaches.com }}</ref><ref>{{cite web|url= https://driving.ca/chevrolet/corvette/auto-news/news/hail-hydra-matic-the-rise-of-the-automatic-transmission |title=Shifting Times: The rise of the automatic transmission|date=6 January 2015}}</ref>

The 1938–1939 [[Buick Special]] was available with another Self-Shifter 4-speed semi-automatic transmission,<ref>{{cite web |title=How Buick Works |url= https://auto.howstuffworks.com/buick.htm |website=howstuffworks.com |access-date=8 August 2020 |language=en |date=5 June 2007}}</ref><ref>{{Cite web |title=1938-Buick-Folder.pdf |url=https://www.xr793.com/wp-content/uploads/2018/10/1938-Buick-Folder.pdf |access-date=16 October 2023 |website=xr793.com}}</ref><ref>{{cite web|url= https://ateupwithmotor.com/terms-technology-definitions/hydramatic-history-part-1/2/|title=Hydra-Matic History: GM's First Automatic Transmission |website=ateupwithmotor.com |date=29 May 2010}}</ref> which used a manual clutch for starting from standstill and an automated clutch for gear changes.

The 1941 [[Chrysler]] [[Vacamatic|M4 Vacamatic]] transmission was a two-speed manual transmission with an integral underdrive unit, a traditional manual clutch, and a fluid coupling between the engine and the clutch.<ref>{{cite web |title=The M6 automatic transmission |url= https://www.allpar.com/mopar/m6.html |website=allpar.com |access-date=9 August 2020}}</ref><ref>{{cite web |title=Chrysler transmissions-Vacamatic semi-automatic |url= http://www.gottransmissions.com/blog/chrysler-transmissions/chrysler-transmissionsvacamatic-semi-automatic |website=gottransmissions.com |access-date=9 August 2020}}</ref><ref>{{cite web |title=How Chrysler Works |url=https://auto.howstuffworks.com/chrysler.htm |website=howstuffworks.com |access-date=9 August 2020 |language=en |date=1 June 2007}}</ref> The two-speed transmission had "high" and "low" ranges, and the clutch was used when the driver wanted to switch between ranges. For normal driving, the driver would press the clutch, select the High range, and then release the clutch. Once the accelerator was pressed, the fluid coupling would engage and the car would begin moving forward, with the underdrive unit engaged to provide a lower gear ratio. At between {{convert|15|and|20|mph|km/h|abbr=on}}, the driver would lift off the accelerator and the underdrive unit would disengage. The Vacamatic was replaced by a similar [[Presto-Matic|M6 Presto-Matic]] transmission for the 1946 model year.

Similar designs were used for the 1941–1950 [[Hudson Motor Car Company|Hudson]] Drive-Master<ref>{{cite web |title=1941–1947 Hudson |url=https://auto.howstuffworks.com/1941-1947-hudson3.htm |website=howstuffworks.com |access-date=8 August 2020 |language=en |date=16 September 2007 |archive-date=20 August 2008 |archive-url=https://web.archive.org/web/20080820183959/http://auto.howstuffworks.com/1941-1947-hudson3.htm |url-status=dead }}</ref><ref>{{cite web |title=Step-Down: The 1948–1954 Hudsons |url= https://ateupwithmotor.com/model-histories/step-down-hudsons/ |website=ateupwithmotor.com |access-date=8 August 2020 |date=6 September 2009}}</ref> and the ill-fated 1942 [[Lincoln Motor Company|Lincoln]] Liquimatic.<ref>{{cite web |title=Automatic Failure: Ford's 1942 Liquamatic Experiment |url=https://www.macsmotorcitygarage.com/automatic-failure-fords-1942-liquamatic-experiment/ |website=macsmotorcitygarage.com |access-date=8 August 2020 |date=7 February 2017}}</ref><ref>{{cite web |title=Automotive History: Lincoln's Liquamatic Drive – Failure to Upshift |url= https://www.curbsideclassic.com/automotive-histories/automotive-history-lincolns-liquamatic-drive-failure-to-upshift/ |website=curbsideclassic.com |date=30 May 2019 |access-date=8 August 2020}}</ref> Both of these combined a 3-speed [[manual transmission]] with automated shifting between the 2nd and 3rd gears, instead of the Vacamatic's "underdrive" unit.

The Packard Electro-Matic, introduced in the 1941 [[Packard Clipper]] and [[Packard 180]], was an early clutchless manual transmission that used a traditional friction clutch with automatic vacuum operation, which was controlled by the position of the accelerator.

=== 1950s–1960s ===
The [[Automotive Products]] manumatic system, available on the 1953 [[Ford Anglia#Anglia 100E (1953–1959)|Ford Anglia 100E]], was a vacuum-powered automatic clutch system that was actuated by a switch that was triggered whenever the gear stick was moved. The system could control the throttle cable (to keep the engine at the required RPM for the gear change) and vary the rate of clutch engagement.<ref>{{cite book |last1=Staton |first1=Abbey |title=Practical Automobile Engineering – Clutch Systems |pages=193–194}}</ref> The successive Newtondrive system, available on the 1957–1958 Ford Anglia, also had a provision for [[Choke valve|choke]] control. A similar product was the German [[Saxomat]] automatic clutch system, which was introduced in the mid-1950s and available on various European cars.<ref>{{cite web |title=Rare Rides: An Incredibly Rare 1965 Lancia Flaminia Super Sport Zagato |url= https://www.thetruthaboutcars.com/2020/05/rare-rides-an-incredibly-rare-1965-lancia-flaminia-super-sport-zagato/ |website=thetruthaboutcars.com |access-date=17 August 2020 |date=14 May 2020}}</ref>

The [[Citroën DS]], introduced in 1955, used a [[Hydraulic machinery|hydraulic system]] with a hydraulically-operated speed controller and idle speed step-up device to select gears and operate the otherwise conventional clutch. This allowed clutchless shifting with a single [[Steering column|column]]-mounted selector, while the driver simultaneously lifted off the accelerator to change gear. This system was nicknamed "Citro-Matic" in the U.S.

For the 1962 model year, [[American Motors Corporation|American Motors]] introduced the E-Stick, which eliminated the clutch pedal in the [[Rambler American]] with standard three-speed manual transmissions.<ref>{{cite book |last1=Kirk |first1=W.R. |last2=Puidokas |first2=S.V. |title=SAE Technical Paper Series |chapter=The Rambler E-Stick Transmission |chapter-url= https://www.sae.org/publications/technical-papers/content/620106/ |publisher=SAE Technical Paper |date=1 January 1962 |volume=1 |doi=10.4271/620106 |access-date=16 November 2020}}</ref> This automatic clutch used engine oil pressure as a hydraulic source and was available for less than $60.<ref>{{cite journal |title=New Rambler "E-Stick" rated big '62 auto news (advertisement) |journal=Popular Mechanics |date=January 1962 |volume=117 |issue=1 |page=223 |url= https://books.google.com/books?id=POEDAAAAMBAJ&q=rambler+e-stick+transmission&pg=PA223 |access-date=16 November 2020}}</ref> Compared to fully automatic transmissions of the time, the E-Stick offered the fuel economy of a stick-shift, with vacuum and electric switches controlling the clutch. The E-Stick three-speed transmission was offered on the larger [[Rambler Classic]] models, along with an overdrive unit.<ref>{{cite web |title=1964 X-Ray Rambler brochure |url= http://oldcarbrochures.org/United%20States/AMC/1964_AMC/1964-X-Ray-Rambler-Brochure/slides/1964_X-Ray_Rambler-20-21.html |website=oldcarbrochures.org |access-date=16 November 2020 |page=20}}</ref> The system was only available with 6-cylinder engines, and the lack of a clutch proved unpopular, so it was discontinued after 1964.<ref>{{cite journal |last1=Whitmyer |first1=Marty |title=Behind the scenes at new car showings |journal=Commercial Car Journal |date=1964 |url= https://books.google.com/books?id=6JknAAAAMAAJ&q=1964+Behind+the+scenes+at+new+car+showings+e-stick |quote=The "E" stick transmission offered by AMC in '64 has been dropped. |access-date=16 November 2020}}</ref>

The 1967 [[Volkswagen]] WSK (''Wandlerschaltkupplungsgetriebe''; English: ''Torque converter shift/clutch gearbox''), used in the [[Volkswagen Beetle|Beetle]], [[Volkswagen Type 3|Type 3]] and [[Volkswagen Karmann Ghia|Karmann Ghia]], was one of the first gearboxes of its kind, with an automatic mechanical clutch and a torque converter. It was also known as the [[Autostick]]. Shifting was done manually by the driver. The automatic mechanical clutch allowed the car to accelerate from a stop, whereas the torque converter enabled it to do so in any gear. Dampening engine vibrations and providing torque multiplication, it functioned as a sort of "reduction gearbox", so the actual mechanical gearbox only needed three forward gears (this is why conventional automatic transmissions with torque converters normally have fewer gears than manual transmissions). The WSK had no "first" gear; instead, the first gear was converted into reverse gear, and the second gear was labeled first (with the third and fourth gears respectively being labeled second and third).<ref>Harald Naunheimer, Bernd Bertsche, Gisbert Lechner: ''Fahrzeuggetriebe – Grundlagen, Auswahl, Auslegung und Konstruktion'', 2nd edition, Springer, Berlin/Heidelberg/New York 2007, {{ISBN|978-3-540-30625-2}}, p. 170–173.</ref>

The [[Powerglide#Torque Drive|Chevrolet Torque-Drive]] transmission, introduced on the 1968 [[Chevrolet Chevy II / Nova#Third generation|Chevrolet Nova]] and [[Chevrolet Camaro (first generation)|Camaro]], is one of a few examples where a semi-automatic transmission was based on a conventional hydraulic automatic transmission (rather than a standard manual transmission). The Torque-Drive was essentially a 2-speed [[Powerglide]] automatic transmission without the vacuum modulator, requiring the driver to manually shift gears between "Low" and "High". The quadrant indicator on Torque-Drive cars was "Park-R-N-Hi-1st". The driver would start the car in "1st," then move the lever to "Hi" when desired. The Torque-Drive was discontinued at the end of 1971 and replaced by a traditional hydraulic automatic transmission. Other examples of semi-automatic transmissions based on hydraulic automatics were the Ford 3-speed Semi-Automatic Transmission used in the 1970–1971 [[Ford Maverick (1970)|Ford Maverick]], early versions of Honda's 1972–1988 [[Hondamatic]] 2-speed and 3-speed transmissions, and the [[Daihatsu]] Diamatic 2-speed transmission used in the 1985–1991 [[Daihatsu Charade]].

=== Other examples ===
[[File:Saab_Sensonic_transmission.jpg|thumb|right|Illustration of Saab's ''Sensonic'' clutchless manual transmission system.]]
{| class="wikitable sortable"
|-
! Years !! Name !! Notes
|-
| 1953–1954 || [[Plymouth (automobile)|Plymouth]] [[Hy-Drive]]|| Torque converter added to a 3-speed manual transmission so it could be driven solely in top gear (to avoid using the manual clutch).
|-
| 1956–1963 || [[Renault]] Ferlec || Automatic electromagnetic clutch. Used in the [[Renault Dauphine]].<ref>{{cite web |title=1956–1968 Renault Dauphine |url= https://auto.howstuffworks.com/1956-1968-renault-dauphine.htm/printable |website=howstuffworks.com |access-date=8 August 2020 |language=en |date=20 August 2007}}</ref><ref>{{cite web |title=Renault Dauphine buyer's guide: what to pay and what to look for |url= https://www.classicandsportscar.com/features/buyers-guide-renault-dauphine |website=classicandsportscar.com |access-date=8 August 2020}}</ref>
|-
| 1957–1961 || [[Mercedes-Benz]] Hydrak || Automatic vacuum-powered clutch, plus a fluid coupling for standing starts.<ref>{{cite web|url= http://www.mbzponton.org/valueadded/maintenance/hydrak.htm |title=Mercedes-Benz Ponton Hydrak Automatic Clutch |first=Jeff|last=Miller|website=mbzponton.org|access-date=24 October 2017}}</ref>
|-
| 1959–???? || [[Citroën]] Traffi-Clutch  || Automatic centrifugal clutch. Used in the [[Citroën 2CV]], [[Citroën Traction Avant]], and [[Citroën Dyane]].
|-
| 1965–1990 || [[HQM Sachsenring GmbH|VEB Sachsenring]] Hycomat || Automatic electro-hydraulic clutch. Used in the [[Trabant 601]].
|-
| 1966–???? || [[Simca]] automatic clutch || Automatic clutch plus a torque converter. Used in the [[Simca 1000]].<ref>{{cite web |title=Theme: Simca – 1965 1000 GLS Short Road Test |url= https://driventowrite.com/2017/03/04/1965-simca-1000-gls-short-road-test/ |website=driventowrite.com |access-date=8 August 2020 |date=4 March 2017}}</ref><ref>{{cite web |title=Simca 1100 |url= https://www.uniquecarsandparts.com.au/car_info_simca_1100 |website=uniquecarsandparts.com.au |access-date=8 August 2020}}</ref><ref>{{cite web|url= https://www.flickr.com/photos/njsimca/3082847153/in/photostream/ |title=Simca 1000 GLA Automatique 1966 lever |publisher=Flickr.com |date=4 December 2008 |access-date=2020-03-01}}</ref><ref>{{cite web |url= http://www.rootes-chrysler.co.uk/simca-cars/simca-1000.html | title = Simca 1000 cars | publisher = VerticalScope |work = Rootes-Chrysler.co.uk | access-date = 8 August 2012 | last = Thompson | first = Andy }}</ref>
|-
| 1967–1977 || [[NSU Motorenwerke|NSU]] automatic clutch || Automatic vacuum-powered clutch plus a torque converter. Used in the [[NSU Ro 80]].
|-
| 1967–1976 || [[Porsche]] Sportomatic || Automatic vacuum-powered clutch plus a torque converter. Used in the [[Porsche 911 (classic)|Porsche 911]].<ref>{{cite web|url= https://www.caranddriver.com/news/a15366473/shift-this-a-history-of-porsches-sportomatic-tiptronic-and-pdk-transmissions/ |title = Shift This: A History of Porsche's Sportomatic, Tiptronic, and PDK Transmissions|date = 10 December 2013}}</ref><ref>{{cite web|url= https://www.total911.com/porsche-911-rs-book-volume-2-now-on-sale/ |title=Porsche 911 RS Book Volume 2 now on sale|date=28 June 2014}}</ref>
|-
|1968–1971
|[[Subaru]] Autoclutch
|Automatic electromagnetic clutch.<ref>{{cite web|title=Subaru 360 Sedan Auto-Clutch Service Manual|url= http://www.mysubaru360.com/manuals_and_documents/Subaru_360_Autoclutch_manual.pdf |access-date=2021-10-18}}</ref> Used in the [[Subaru 360]].<ref>{{cite web|date=6 January 2021|title=Once "Cheap and Ugly," the Subaru 360 is having an unexpected moment|url= https://www.hagerty.com/media/valuation/once-cheap-and-ugly-the-subaru-360-is-having-an-unexpected-moment/ |access-date=2021-10-18|website=Hagerty Media|language=en-US}}</ref>
|-
| 1968–1976 || [[Volkswagen]] [[Autostick]]|| Automatic electro-pneumatic clutch plus a torque converter. Used in the [[Volkswagen Beetle]] and [[Volkswagen Karmann Ghia]].<ref name="VWhalb">{{cite web | url = http://www.kaeferclub-siegerland.de/technik/automatic.htm | archive-url = https://web.archive.org/web/20130410022102/http://www.kaeferclub-siegerland.de/technik/automatic.htm | archive-date = 10 April 2013 | title = VW Automatic – der Käfer mit halbautomatischem Getriebe | trans-title = VW Automatic – the Beetle with a semi-automatic transmission | language = de | last = Dingeldein | first = Wolfgang | date = 2011 | work = Käfertreter Siegerland }}</ref>
|-
| 1971–1980 || Citroën C-matic || Automatic clutch plus a torque converter. Used in the [[Citroën GS]] and [[Citroën CX]]. Originally called Convertisseur in GS models.
|-
| 1991–1993 || [[Ferrari]] Valeo|| Automatic electro-mechanical clutch. Used in the [[Ferrari Mondial#Mondial t|Ferrari Mondial t]].<ref>{{cite web|url=https://www.vwvortex.com/threads/the-archive-1991-ferrari-mondial-t-with-valeo-automatic-clutch.4519537/|title=The Archive – 1991 Ferrari Mondial t – with Valeo...|website=VW Vortex – Volkswagen Forum|date=3 May 2011 }}</ref><ref>{{cite web|url=https://www.ferrari.com/en-US/auto/mondial-t|title=Ferrari Mondial T (1989) - Ferrari.com|website=www.ferrari.com}}</ref>
|-
| 1992–1998 || [[Ruf Automobile|RUF]] [[Fichtel & Sachs|{{abbr|EKS|Electronic Clutch System}}]]|| Automatic electro-hydraulic clutch. Used in the [[Ruf BTR#BTR 3.8|Ruf BTR]]<ref>{{cite web|title=RUF Automobile GMBH – Manufaktur für Hochleistungsautomobile – History|url= https://ruf-automobile.de/en/performance/historie/}}</ref> and [[Ruf BTR2]].
|-
| 1993–1998 || [[Saab Automobile|Saab]] Sensonic || Automatic electro-hydraulic clutch.<ref>{{cite web|date=13 December 2005|title=Saab Shelves Sensonic Transmission|url= https://www.autonews.com/article/19980216/ANA/802160766/saab-shelves-sensonic-transmission}}</ref><ref>{{cite web| url = https://www.orlandosentinel.com/news/os-xpm-1994-05-12-9405110114-story.html| title = SAAB DEVELOPS STICK WITH NO CLUTCH – Orlando Sentinel| date = 12 May 1994}}</ref> Used in the [[Saab 900 NG]].
|-
| 2020–present || [[Hyundai Motor Company|Hyundai]]/[[Kia]] {{abbr|iMT|Intelligent Manual Transmission}}|| Automatic electro-hydraulic clutch. Used in the [[Hyundai Venue]], [[Hyundai i20]], and [[Kia Sonet]]. The gear stick has a shift pattern similar to a fully manual car, unlike AMTs with only sequential gear selection.<ref>{{cite web|date=10 July 2020|title=Hyundai Venue Offers Manual Transmission With No Clutch Pedal|url= https://www.motortrend.com/news/hyundai-venue-imt-clutchless-manual-transmission/ |access-date=2021-10-18 |website=MotorTrend|language=en}}</ref>
|}