Manual
(Also known as the split case 5 speed or TY752-TY754-TY757)
The following information may give you some understanding of what you may be experiencing with your Subaru gearbox.
Abnormal noises would be the most common complaint of the Subaru 5 Speed non-turbo manual gearboxes due to bearing failure as the gearbox/transmissions ages. Subaru viscous couplings also do fail in both the 5 speed gearbox causing binding or locking when cornering, especially as the component generates heat. Generally, gear selection and shifting issues are minimal.
Some Subaru 5 speed manual gearboxes have problems with wearing of the front gearbox case, at the snout area where the clutch release bearing runs; this is normally due to the lack of lubrication and or the incorrect type of grease used in assembly.
(Also known as the STi 6 Speed or TY856)
The following information may give you some understanding of what you may be experiencing with your Subaru gearbox.
Norrie has an extensive experience in diagnosis and repairs of the Subaru 6 speed gearbox and over the years of overhaul, he has identified the following issues.
Applicable to the following models;
2001 STi EJ207, 2002 STi EJ207, 2003 STi EJ207, 2004 STI EJ207, 2005 EJ207
2006 STI EJ257, 2007 STi EJ257, 2008 STi EJ257, 2009 STi EJ257, 2010 STi EJ257
2011 STi EJ257, 2012 STi EJ257, 2013 STi EJ257, 2014 STi Ej257, 2015 STi Ej257
The most common complaint of the Subaru 6 speed is gear selection or gear crunching when upshifting; this is generally due to worn components such as Gear slider, gear dog teeth wear, and this in turn causes the shifting fork pads to wear out.
Another common symptom is the gear selector jumping out of gear; this is also generally caused by component wear, however in some cases when this occurs after overhaul, it is normally related to gear set alignment. The Subaru 6 Speed requires specialised tools to set up gear selector alignment correctly. We also offer this service to trade customer who may not have these tools or experience to complete such a job.
Gear breakage of the 6 Speed gearbox is limited as these gearboxes are very strong. Modified high hp applications, exceeding 400 kW normally breaks the tall ratio gear sets.
Centre differential binding is experienced in both the viscous coupling centre differentials and DCCD units as the components wear. We have different solutions to rectify these problems as the operation of these centre differentials are totally different in operation although the theory is pretty much the same.
(Also known as TY751)
The following information may give you some understanding of what you may be experiencing with your Subaru gearbox.
The TY751 is the latest designed 6 speed manual gearbox developed by Subaru. In appearance, it is very similar to the earlier designed 5 speed Split case gearbox but has some new developments. The TY751 incorporates no mechanical linkage between the cabin gear selector and the gearbox itself, promoting less gearbox noise into the vehicle’s cabin. Currently and since the production of this Subaru gearbox, we have seen limited internal problems. The most common issues are jumping or difficulty to select the reverse gear and centre differential/viscous coupling binding/locking when turning. Generally, this gearbox is quite reliable.
As this gearbox is also found in WRX MY13, gear breakage is not so common mainly due to increase gear width over the 5 speed Subaru manual turbo gearbox.
(Also known as the 6 Speed or TL70 made by Aisin)
This unique style of Gearbox used for the first time by Subaru is the RWD 6 Speed TL70 produced by Aisin. Unlike all other model Subaru models in Australia that use an All-Wheel Drive System, this gearbox contains no centre differential or viscous coupling.
The TL70 is compact in design and requires attention to detail when overhauling or repairing. The most common complaint is gear shift baulking/crunching when up-shifting. Some synchro-cones have been revised from the first released gearbox and it seems to be quite successful. Gear breakage is seen in higher output applications. There are occasional complaints of gearbox noise and gearshift rattle. Gearshift rattle is normally an external problem and most times pointed to the slide mechanism in the gear shifter.
Automatic
(Also known as the 4EAT & R4AX)
The 4 Speed Subaru Automatic Transmission is one of the longest serving transmissions that Subaru have used. First equipped in the newly released generation 1 Liberty, the E4AT proved to be quite a reliable transmission with only small issues associated with the Oil pump gasket that was resolved early in the transmission’s life. The first real major change to the Subaru 4 speed Transmission was in the MY04, generation 3 Liberty & Outback where the transmission took on a full electronic valve body.
Accumulator valves were discontinued with direct solenoid valves controlling oil pump pressure directly in turn creating a much nicer, smoother direct gear change. The new transmission was named the D4AT “Direct/Dynamic” Control transmission.
Today, the most common faults with the D4AT is “tight corner braking” Torque converter failure, Valve body contamination, and Low clutch seal leakage causing delayed drive. All in all, the D4AT Subaru transmission is a good reliable transmission that does not give a whole lot of problems.
(Also known as the D5AT)
The Subaru 5 speed Transmission was first seen in the MY04 3.0lt Outback. This transmission has had a number of revisions throughout its time. The main changes to this transmission have been in the valve body design.
Contamination and sensor faults poses the biggest problems. Torque converter vibration during slip lockup control has also called for some revisions.
This transmission’s gearshift control is above average and is nicely geared to the 2.5 limited S edition Forester XT, 3.0lt and 3.6 Variant Liberty and Outback.
(Also known as Lineartronic)
In MY10 Liberty & Outback a new direction in transmission technology was introduced, a continually variable Transmission named “Lineartronic” was adapted with the vision of a transmission that would be around moving into the next decade.
The Lineartronic transmission TR690 series 1 transmission found in MY10-11 models had some issues with stalling upon stopping, some internal seals leaking and valve body issues. The major problem seen with this transmission is the internal failure of the CVT due to mechanical workshops draining the transmission oil and refilling the transmission with conventional ATF oil and not the specialised Lineartronic oil.
The smaller TR580 CVT transmission has adopted a lot of revisions over the TR690, a more compact, lighter transmission developed to reduce weight and improve fuel consumption in most of the non-turbo Subaru models. Minimum problems are currently seen with this transmission. The most common complaint is CVT tuning (surge) on light throttle and valve body problems with some stalling issues noted.