The 2010 Subaru Forester uses a cartridge-style oil filter inside a housing, not a traditional spin-on canister.
On the 2010 Forester with the 2.5-liter engine, the filter is a replaceable cartridge located inside a small oil-filter housing. Service involves removing the housing cap, pulling out the old cartridge, installing a new cartridge, and replacing the housing’s O-ring. Always verify the exact part number for your engine code through the owner's manual or a trusted parts lookup, as specifications can vary by model and production run.
Filter type and replacement basics
Knowing the right filter type and where it’s located helps avoid mistakes during maintenance. The cartridge sits inside a housing on the engine and is accessed by removing the cap with a suitable tool. You’ll replace just the cartridge and the O-ring, not a full canister.
What you’ll need for the replacement:
- Cartridge-style oil filter compatible with the Forester’s EJ-series/2.5L engine (OEM Subaru or a reputable aftermarket cartridge designed for Subaru EJ/FB engines)
- New O-ring for the oil filter housing cap
- The correct engine oil and an appropriate oil filter (per the owner’s manual)
- Oil drain pan, rags, and gloves for cleanliness
- Tool to remove the housing cap (commonly a 24 mm socket or wrench)
Using the correct cartridge and replacing the O-ring helps ensure a proper seal and prevents leaks during and after the service.
Replacement steps (overview)
To perform the change, follow these general steps. Always refer to the service manual for your exact year/model if available.
- Warm up the engine, then park on a level surface and place a drain pan beneath the oil pan.
- Drain the engine oil by removing the drain plug and allowing the oil to finish dripping.
- Loosen and remove the oil-filter housing cap using the proper tool (typically a 24 mm socket).
- Remove the old cartridge from the housing and wipe the inside of the housing clean.
- Install the new O-ring on the housing cap, then place the new cartridge into the housing.
- Reinstall the housing cap and torque to the manufacturer’s specification; refill the engine with the correct amount and grade of oil, then check for leaks and reset the oil-change indicator if applicable.
Following these steps precisely helps ensure proper filtering and oil pressure after a change.
Where to buy and how to verify part numbers
Because Subaru uses a cartridge-style filter that can vary by engine code and production run, it’s important to verify the exact part number before purchasing. Use these approaches to confirm compatibility:
- Check the owner’s manual or the intake side of the old filter for the exact part number
- Use a reputable parts retailer’s lookup by year, make, model, and engine code (EJ25 for many 2010 Foresters)
- Bring the old filter to the parts counter for an in-person cross-reference
- Consult Subaru’s official parts catalog or ask a dealer technician if you’re uncertain
OEM cartridge oil filters are widely available, and many reputable aftermarket brands publish compatibility charts. If you’re unsure, a trusted mechanic can confirm the correct cartridge and O-ring for your specific Forester’s VIN.
Summary
The 2010 Subaru Forester uses a cartridge-style oil filter housed in a dedicated filter housing rather than a spin-on canister. Replacement involves removing the housing cap, swapping in a new cartridge and O-ring, and refitting the cap, followed by oil top-up and leak checks. Verify the exact part number for your engine code through official catalogs or a parts retailer to ensure a proper fit.