Impreza WRX STi and Legacy specifications B
There are three six speed manual transmissions currently available for USDM Subarus. The STi and Legacy Spec B are the two vehicles that received them. The STi's 6MT has undergone various changes throughout the years, but have always had a limited slip front differential and the DCCD. In 2006, The STi's 6MT underwent some changes that included making the center differential a limited slip unit 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 DCCD, and neither the front nor center differentials are limited slip units. The Spec B's 6MT is still highly prized; however, because of its longer ratios than those found in the STi, while still retaining much of the STi unit's robustness.
|Model||1st||2nd||3rd||4th||5th||6th||Reverse||Final Drive||DCCD||Front Diff||Center Diff|
|US Impreza WRX STi MY04 TY856WH3MA||3.636||2.375||1.761||1.346||0.971||0.756||3.545||3.900||35/65||A.P. Suretrac||automatic DCCD system|
|US Impreza WRX STi MY04 late TY856WH4MA||3.636||2.375||1.761||1.346||0.971||0.756||3.545||3.900||35/65||A.P. Suretrac||automatic DCCD system|
|US Impreza WRX STi MY05 TY856WW6MA||3.636||2.375||1.761||1.346||0.971||0.756||3.545||3.900||35/65||Helical LSD||automatic DCCD system|
The new 2010 Legacy and Outback models will offer a six-speed manual as one of the two transmission options in the base 2.5i, 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 of construction with the STI's 6MT transmission. The transmission uses a cable shifter, unlike all previous designs that use a direct mechanical linkage.