SUBARU TECHNICAL SERVICE BULLETIN
APPLICABILITY: ALL VEHICLES EQUIPPED WITH TURBO
SUBJECT: TURBOCHARGER MESH FILTER SCREEN
It is possible that the turbo oil supply mesh filter, which is located inside the banjo bolt that secures the turbocharger oil supply pipe to the back of the right cylinder head, may become clogged thereby preventing oil supply to the turbo resulting in failure. Therefore it is required that this filter screen be checked for obstructions any time a Turbocharger is being replaced for failure.
(how about just replacing this part every 60k?)
If the mesh screen is found to be obstructed it should be cleaned or replaced. Obstructions could be sludge due to poor engine oil maintenance or harsh driving conditions. Further diagnosis may be required if significant amounts of sludge, metal, and/or other materials are found in the mesh filter screen. In any turbocharger replacement, sufficient oil pressure to the turbocharger should be verified. Please consult the service manual for the appropriate specification.
Note: The mesh filter screen is only available with a replacement banjo bolt. (P/N 14445AA090) Tightening torque: 29 N-m (3.0 kgf-m 21.4 ft-lb).
Note: Anytime the banjo bolt is removed or replaced, both copper washers must be replaced with new ones.
Make sure the mesh filter screen is installed in the proper direction; incorrect installation will prevent oil supply to the turbocharger.
Do not confuse the turbocharger oil supply mesh filter screen with the Active Control Valve System (AVCS) union screw mesh filter screen.
Refer to Service Bulletin 02-97-05, dated 10/06/05.
Note: In addition, if the turbocharger is replaced, it is required that the oil pan be removed to inspect for sludge, metal, and/or other materials. If found and not removed, catastrophic engine damage could occur including the failure of the replacement turbocharger. Oil supply/returns lines, oil passages, etc should also be checked if questionable. Don't rule out a restricted oil filter. The materials found in the oil pan could also indicate the need for further diagnosis of other engine components.
Engine Oil and Oil Filter:
Due to heat generated by the turbocharger and carbon deposits contained in exhaust gas, the oil in a turbocharged engine will deteriorate faster that the oil in a naturally aspirated engine. Therefore, all turbocharged vehicles are classified as "severe driving condition" vehicles and special care should be taken to use the proper grade. The recommend oil and filter change interval for turbocharged vehicles is every 3,750 miles or four months, whichever comes first.
Proper lubrication of the turbocharger requires high-quality engine oil. Some do not provide enough lubriation performance or durability when used in turbocharged engines. Using poor quality oil or oil not designed for turbo engines may cause damage to the turbocharger and other engine components. Consequently, it is critical to follow Subaru vehicle owner's and service manuals for recommended oil grade and viscosity.
The Subaru Genuine Oil Filter is the oily filter that Subaru has tested to meet requirements for filtration and flow. Aftermarket oil filters may have different filtration performance and relief-valve opening pressure, which could affect filter and engine performance.
(NOTE THIS APPLIES TO ALL SUBARU TURBOCHARGED ENGINES REGARDLESS OF YEAR OR MODEL)