Information that I have collected for my 2005 Subaru Outback XT Limited.
Update: Engine has blown. Currently at Horizontal Motor Sports.
EJ255 Version 1: Used in the 2005 and 2006 Legacy, as well as the 2004 and 2005 Forester. This engine uses the AB440 shortblock, which is the same shortblock as the 2004–2006 STI EJ257. The heads on these EJ255 are the AB650s, while the US 04–06 STI is the familiar AB640/910. The cams are the same between the EJ255 Version 1 and the EJ257.
A list of things to check and/or change out.
- Banjo bolt
- Oil and filter
- Fluid change
- Rear differential
- Air filter
- Spark plugs
- Coil packs
- Seafoam (Top-end cleaning?)
- Inner/Outer tie rods and ball joints
Oil and filter
Popular recommendation seems to be Full Synthetic with turbo cars.
- K&N HP–1008 Filter
- Rotella T6
Transmission and Rear differential
Both use synthetic 75W–90 gear oil. Make sure its GL–5 rated.
You’ll need 4QTs of fluid for the front and 1QT for the rear.
You will need a T70 Torx bit to take off the front drain plug. Remove dipstick, remove and clean plug, drain fluid, re-install plug, use funnel and fill, then re-install dipstick. Check levels afterwards.
The rear plugs are 1/2". A pump will be useful for flushing the rear fluids. Remove both plugs, drain, then pump/fill until fluid runs clean out of bottom hole, insert bottom plug, pump until fluid comes out of top hole, then plug top hole.
If you have a torque wrench:
- Oil Drain Plug: 33 ft-lb
- Transmission Drain Plug (T70): 50.6 ft-lb
- Rear Drain and Filler Plugs: 36.2 ft-lb
- Skid plate
- Sway bar
The stock uppipe comes with a catalytic converter that is known to disintegrate and send pieces into your turbo, which then feeds into your engine.
It should be replaced with an uppipe that does not have a catalytic converter and it does not require a ‘bung’ for the EGT sensor.
The EGT sensor is only there to monitor whether the cat is working properly. You can disconnect the sensor and use a resistor to trick the ECU to not throw a code.