Subaru motor vehicles have used manual, conventional automatic, and continuously variable (CVT) transmissions. Subaru manufactures its own manual and CVT transmissions (for non-Kei cars). Since the 2014 model year, the conventional automatic transmissions in North American-spec Subaru vehicles have been replaced with Lineartronic CVTs (with one exception: the BRZ)
Subaru built their own four-speed automatic transmission based on the old Jatco design. It was available in FWD and Full-time awd.
ACT-4 or VTD
Subaru uses two types of traction delivery systems, called Active Torque Split (ACT), or the performance oriented Variable Torque Distribution, called VTD. ACT drives the front wheels directly and the rear wheels through a hydraulic clutch. The control unit monitors several factors including vehicle speed, gear position, and wheel speed and then varies the application of the clutch based on a model stored in memory. The effect is a constantly and actively changing torque to the rear wheels anywhere from a few percent to fully locked. The control unit can and does alter torque several times per second. Vehicles with higher power engines use a more aggressive model resulting in generally higher rear engagement. Later attempts at reducing customer confusion resulted in torque split numbers being given, but these have no meaning as there is no mechanical or other device to provide a static starting point for the control unit. This system is the more commonly used setup used on most Subaru products after its introduction on the XT6. VTD adds a twin planetary center differential to the clutch and therefore has a static, starting torque split calculated on the planetary gear ratio, with the most common being 45:55. The active clutch operation is similar to the ACT system, although the clutch is used to suppress differential action instead of as the differential itself. VTD was introduced on the Alcyone SVX in 1991 and is usually found in performance models equipped with a turbocharger, along with the VDC outback and USDM 2003-2004 Legacy GT/2.5GT. ACT and VTD are found in both generations of the 4 speed while the 5 speed uses only VTD.
4EAT
This transmission was released in 1988 for use in the Subaru XT6 and Leone Touring Wagon. The bellhousing and input shaft were changed for the Subaru EJ engine, the first was used until about 1998, when a major redesign of the holding devices was released. The second generation saw use until 2008.
The final use of the 3.272 final drive ratio (Part 38100AB740) was in the 2009 Legacy 3.0R Limited sedan (but not the regular R sedan), the 2009 Outback 2.5XT Limited (but not the regular XT), and the 2009 Outback 3.0R Limited (but not the regular R or LL Bean).
The first use of the 3.083 final drive ratio (Part 38100AB730) was in the 2007 Legacy GT. The final use was in the 2014 Legacy and Outback with the EZ36 engine.
Subaru developed a CVT for the Subaru Justy to gain reasonable acceleration and fuel economy from its small three cylinder engine. It employs a push-belt system and comes with an optional 4WD unit that engages the rear wheels when a button on the shifter is depressed. It also has a 'sport mode' that, when activated, nearly doubles engine RPM for better torque distribution when towing or going uphill. The Shift Indicator reads P-R-N-D-Ds, Ds stands for Drive Sport, which doubles engine RPM. The CVT transmission proved unreliable after accumulating high mileage, causing Subaru to stop exporting cars with CVTs outside of Japan until the fifth generation Legacy/Outback. Subaru did continue to build Kei cars with CVTs, only for sale in Japan. In addition to improving the design of the transmission over the years, Subaru has supplied other companies with CVTs, as well. The Justy ECVT was also available with hydraulically actuated 4WD (unlike the 5MT Justy, which has pneumatic actuation) in November 1988, this model was called the Justy 4WD ECVT.
The fifth generation Legacy/Outback and the Subaru Exiga received a newly revised CVT under the Lineartronic name. It is a metal chain, pulley-based CVT, which is considered the most reliable, due to the simplicity of the pulley system and durability of the metal chain. In addition, the metal chain pulley system is generally quieter than other CVT designs.
In the US, the Lineartronic is available with the 2.5i engine in the Outback, Legacy and Forester(2014), and the 2.0 FB engine in the Impreza and slightly modified for the XV Crosstrek. In SE Asia this transmission is also available for the 2.0i engine for the 2010 and later Legacy Asia spec. Subaru claims that the transmission provides "uninterrupted power that maximizes fuel efficiency while keeping the engine at the optimal rev range". EPA mileage estimates for the CVT with the 2.5i, naturally aspirated based engine, claim 30 MPG highway (29 Outback, 31 Legacy).[1]
Lineartronic uses a specially modified torque converter to connect the engine to the transmission. It can slip like a traditional torque converter, but remains locked under all conditions except when coasting or traveling at very low speed. The persistent lockup condition under acceleration provides the efficiency and control of a clutch while still behaving much like a traditional planetary automatic transmission. The transmission can also be manually controlled by the driver by providing the ability to select 6 or 7 (if paired with a Diesel engine[2]) or 8 different "virtual" gears, where the transmission will hold a particular ratio.
Subaru owners have complained about problems with the Lineartronic CVT transmissions[3] and Subaru extended the warranty for cars from model years 2010 to 2018. [4][5][6]
After its introduction in 1984, the Justy was also available with 4WD and thus a different gearbox. The gear ratios for this gearbox were altered slightly. In 1994 the normal/FWD gearbox was dropped; one could only get a 4WD gearbox by then.
It is notable to mention that only Turbo vehicles received a hydraulic clutch until 1995. Also, in 1998 Subaru changed from a push-style clutch to a pull-style, on turbo models, requiring minor bellhousing and fork changes.
1st 3.454 2nd 1.888 3rd 1.296 4th 0.972 5th 0.780 6th 0.695 R 3.686 Final 4.444:1[9]
SJ Forester 2.5i, Impreza WRX STi and Legacy spec. B
There are several six speed manual transmissions currently available for USDM Subarus, found in the STi, Legacy Spec B, and 2015 WRX. The STi's 6MT has undergone various changes throughout the years, but have always had a limited slip front differential with Driver Controlled Center Differential (DCCD). In 2006, The STi's 6MT underwent some changes that included increasing the preload on the center differential and a slight lengthening of some gears. The Spec. B's 6MT has different gear ratios (specifically 6th gear being longer) than the STi's unit, does not have the STi's DCCD system but rather a standard Subaru center viscous coupling center differential, and the front differential is not a limited slip unit. The Spec B's 6MT ratios are highly prized by some due to its longer ratios than those found in the WRX STi, while still retaining much of the STi unit's robustness.
Gear Ratios: 1st 3.636 2nd 2.375 3rd 1.761 4th 1.346 5th 0.971 6th 0.756 Rev 3.545 (This applies to the 04-05 STi, and not the Legacy Spec B)
Gear Ratios: 1st 3.636 2nd 2.235 3rd 1.590 4th 1.137 5th 0.891 6th 0.707 Rev 3.545 (This applies to the 06+ STi, and not the Legacy Spec B)
Early 2004 WRX STi models came with axle stubs inserted in the transmission with female front axles. Late 2004 WRX STi models came without the stubs and instead had male front axles.
The 2004 and 2005 model WRX STi 6MT was a final drive of 3.90. In 2006 and 2007 the 6MT came with a final drive of 3.545 which made the 2006 and 2007 much sought after for the non-STi WRX owners as a transmission swap. This is due to the R160 rear differential 3.545 final drive of most of the non-STi WRXs.
Pre 2008 model year WRX STi 6MT versions utilizes a self-contained oil system with a trochoidal oil pump mounted in the rear of the transmission case. This capability was removed for 2008 and later years. Subaru chose a simplified splash/scraper lubrication system. However, the oil pump-equipped 6MT version is still listed as the transmission of choice in the STi Group N parts system, even for the 2015+ model year WRX STi, with the option of mounting a homologated transmission oil cooler. Subaru Tecnica International's choice to continue using the oil pump-equipped 6MT for Group N racing, originally for the 2007 model years and older, led to the assessment that oil pump transmissions are still favored for motorsport/heavy duty applications. As such, 2008+ WRX STi 6MT with the splash/scraper oil system is a byproduct of a cost-saving measure from Subaru, which may have determined an intricate lubrication system was not necessary for a showroom/production vehicle until it would be converted for motorsport use.[10]
Model
1st
2nd
3rd
4th
5th
6th
Reverse
Final Drive
Torque Split F/R
Front Diff
Center Diff
Rear Diff
Impreza WRX STi MY01-04 TY856WH3MA
3,636
2,375
1,761
1,346
0,971
0,756
3,545
3,900
35/65
A.P. Suretrac
Viscous Coupling (DCCD system MY03 onwards)
Viscous LSD
Impreza WRX STi MY01-04 TY856WH4MA
3,636
2,375
1,761
1,346
0,971
0,756
3,545
3,900
35/65
A.P. Suretrac
automatic electromechanical DCCD system
Viscous LSD
Impreza WRX STi MY05-07 TY856WW6MA
3,636
2,375
1,761
1,346
0,971
0,756
3,545
3,900
35/65
Helical LSD
automatic electromechanical DCCD system
Viscous LSD
WRX STi MY08-14 TY856UB1KA
3,636
2,235
1,590
1,137
0,891
0,756
3,545
3,900
41/59
Helical LSD
electronic (08-16 electromechanical) DCCD system
Torsen LSD
WRX STi MY15-18 TY856UW6AA
3,636
2,235
1,521
1,137
0,971
0,756
3,545
3,900
41/59
Helical LSD
electronic (08-16 electromechanical) DCCD system
Torsen LSD
WRX STi MY19-21 TY856UW6AB
3,636
2,235
1,590
1,137
0,971
0,756
3,545
3,900
41/59
Helical LSD
electronic (08-16 electromechanical) DCCD system
Torsen LSD
SJ Forester 2.5i 2014-2018
3.454
1.888
1.296
0.972
0.780
0.695
3.686
4.444:1
50/50
viscous coupling
viscous coupling
viscous coupling
BM/BR Legacy/Outback
The 2010-2014 Legacy and Outback models offer a six-speed manual as one of the two transmission options in the base 2.5i and 2.5i Premium and is the only option for the Legacy GT model. This transmission is an evolution of the 5MT split-case design, and does not share any parts with the STI's 6MT transmission. The transmission uses a cable shifter, unlike previous designs that use a direct mechanical linkage.
The 2015 WRX has a new 6-speed cable-shifted manual transmission behind the new FA20DIT boxer engine. This transmission uses a viscous limited slip center differential with a 50/50 torque split similar to the 5MT found in previous WRX's. Reverse is located to the right of 6th gear, and is accessed by lifting a lockout ring below the shift knob, similar to the STi 6MT.
Like the Legacy/Outback, the WRX 6MT is of a split-case design similar to the older 5MT and does not share any internal commonality with the WRX STi 6MT.
The 2018-2023 Crosstrek featured a six-speed cable shifted manual transmission. It is similar in design to the six-speed transmission found in the 2010-2014 Outback. Subaru stopped offering the Crosstrek with a manual transmission starting with the 2024 model year.[14] This transmission is desirable for its low first gear ratio and compatibility with older Subaru platforms, such as the 3rd generation Outback (2005-2009).[15]
The Subaru Forester is a compact crossover SUV that has been manufactured by Subaru since 1997. The first generation was built on the platform of the Impreza in the style of a taller station wagon, a style that continued to the second generation, while the third-generation model onwards moved towards a crossover SUV design. A performance model was available for the second-generation Forester in Japan as the Forester STi.
The Subaru Impreza is a compact car that has been manufactured by the Japanese automaker Subaru since 1992. It was introduced as a replacement for the Leone, with the predecessor's EA series engines replaced by the new EJ series. It is now in its sixth generation.
The Subaru Leone is a compact car produced by the Japanese car manufacturer Subaru from 1971 to 1994. The word leone is Italian for lion.
The Subaru Justy is a subcompact hatchback that has been sold by Japanese automobile manufacturer Subaru since 1984. Subaru manufactured the Justy from 1984 to 1994; since then it has sold rebadged versions of other vehicles under the Justy nameplate. The company introduced the latest iteration, a rebadged Daihatsu Boon, at the 2007 Frankfurt Motor Show with a 1.0 or 1.2-liter straight-three engine, front/four wheel drive, electronically controlled continuously variable transaxle, or a 5-speed manual transaxle. For the 2010 model year, the Justy was replaced with the Subaru Trezia. The Justy nameplate was revived in November 2016 as a rebadged Toyota Tank and its twin counterpart the Toyota Roomy and Daihatsu Thor.
Subaru Tecnica International, or STI, is Subaru Corporation's motorsports division. STI, along with Prodrive of the UK, specialized in the preparation of a variety of vehicles for the Subaru World Rally Team which competed in the World Rally Championship (WRC). It was founded in 1988 by Subaru Corporation, the parent company of Subaru, to promote the company's performance-oriented identity.
The Subaru Impreza WRX STI is high performance specification model of the Subaru Impreza compact car line, manufactured by Japanese automaker Fuji Heavy Industries Subaru.
Torsen Torque-Sensing is a type of limited-slip differential used in automobiles.
The Subaru EJ engine is a series of four-stroke automotive engines manufactured by Subaru. They were introduced in 1989, intended to succeed the previous Subaru EA engine. The EJ series was the mainstay of Subaru's engine line, with all engines of this series being 16-valve horizontal flat-fours, with configurations available for single, or double-overhead camshaft arrangements. Naturally aspirated and turbocharged versions are available, ranging from 96 to 310 hp. These engines are commonly used in light aircraft, kit cars and engine swaps into air-cooled Volkswagens, and are also popular as a swap into copy wasserboxer engined Volkswagen T3/Vanagon. Primary engineering on the EJ series was done by Masayuki Kodama, Takemasa Yamada and Shuji Sawafuji of Fuji Heavy Industries, Subaru's parent company.
The Subaru Legacy is a mid-size car built by Japanese automobile manufacturer Subaru since 1989. The maker's flagship car, it is unique in its class for offering all-wheel drive as a standard feature, and Subaru's traditional boxer engine. The Legacy was sold as the Liberty in Australia out of deference to Legacy Australia, an organisation dedicated to caring for the families of military service veterans.
The first generation Subaru Legacy is a mid-size family car / wagon developed by Fuji Heavy Industries. The Legacy was an all new model, and was considered a notable departure from Subaru products in the past.
Subaru launched the third generation Japanese and world-market Legacy in June 1998, while the North American model was introduced in May 1999 for the 2000 model year. In all markets except for the United States, production lasted through 2002, with a limited production Blitzen model sold mid-cycle under the 2003 model year in Japan. Production in the United States lasted through 2004.
The fourth generation of the Subaru Legacy was introduced in 2003 and saw a complete redesign of the Legacy on an all-new platform. Development began by the beginning of 1999, with styling freeze in early 2001 and engineering sign-off in 2003.
Subaru is the automobile manufacturing division of Japanese transportation conglomerate Subaru Corporation, the twenty-first largest automaker by production worldwide in 2017.
The second generation of the Subaru Impreza compact car was introduced in 2000 and manufactured up to 2007 by Subaru in Ota, Gunma, Japan, in both sedan and five-door wagon bodystyles, as well as two intermediate facelifts throughout its lifespan.
The Subaru Levorg is a mid-size car manufactured since 2014 by Subaru. According to the company, the name Levorg is a blended word or portmanteau of three words: legacy, revolution and touring. The first Levorg shares its platform with the Impreza/WRX and the Legacy. The second generation Levorg sits on the Subaru Global Platform used by the majority of Subaru's family cars.
The Subaru FA engine is a gasoline boxer-4 engine used in Subaru and Toyota automobiles. It is a derivative of the FB engine, with efforts to reduce weight while maintaining durability as the main design goals. Although the FA and FB engines share a common platform, the FA shares very little in dedicated parts with the FB engine, with a different block, head, connecting rods, and pistons.
The Symmetrical All-Wheel Drive is a full-time four-wheel drive system developed by the Japanese automobile manufacturer Subaru. The system consists of a longitudinally mounted boxer engine coupled to a symmetrical drivetrain with equal length half-axles. The combination of the symmetrical layout with a flat engine and a transmission balanced over the front axle provides optimum weight distribution with low center of gravity, improving the steering characteristics of the vehicle. Ever since 1986, most of the Subaru models sold in the international market are equipped with the SAWD system by default, with the rear wheel drive BRZ and kei cars as the exceptions.
The Subaru Crosstrek is a compact crossover SUV produced by Subaru since 2012. It is a successor to the Outback Sport in the United States and Canada, and the Impreza XV globally. Like the Outback Sport, the Crosstrek is a lifted Impreza hatchback with minor differences, though with a more substantial lift than the Outback Sport.
The Subaru WRX is an all-wheel drive sport compact car manufactured by the Japanese automaker Subaru, originally based on the Impreza created for the World Rally Championship in 1992. Subaru claimed the name WRX stands for "World Rally eXperimental". Starting with the 2015 models, the WRX lineup has been split from the Impreza, with a different body style that is not offered as an optional hatchback/wagon, being introduced as the separate Levorg model.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
