The oil filter location and part number for your Subaru Outback
Your Subaru Outback's oil filter sits on the driver's side of the engine, below the intake manifold. On most model years, you access it from underneath the vehicle or by removing the undertray — you will not reach it from the top. The filter is a cartridge type (not a spin-on canister), which means it lives inside a plastic housing that you unscrew rather than twisting off the filter itself.
The part number depends on your model year. Subaru part number 16510AA051 fits 2015–2024 Outbacks with the 2.5-liter engine. If you own an older model or a different engine size, check your owner's manual or call a Subaru dealer with your vehicle identification number (VIN) to confirm the exact part. Using the wrong filter can affect oil flow and engine protection.
You can buy Subaru genuine filters from a dealer, or use aftermarket equivalents from brands like Fram, Bosch, or Mobil 1 that cross-reference to your model year. Genuine Subaru filters typically cost $12 to $18, while quality aftermarket filters run $8 to $15. Both work well if they meet Subaru's specifications.
Key Takeaways
- The Subaru Outback uses a cartridge-style oil filter located on the driver's side of the engine, accessed from underneath the vehicle.
- Part number 16510AA051 fits 2015–2024 Outbacks with the 2.5-liter engine; confirm your exact part number using your VIN before purchasing.
- You will need an oil filter wrench (usually 74 mm or 86 mm, depending on year) and a drain pan, plus new crush washers for the drain plug.
- The filter housing is hand-tight when properly installed — do not over-tighten, as this can damage the plastic threads.
What tools and supplies you need
To replace the filter yourself, gather an oil filter wrench (the size varies by model year — most Outbacks use either 74 mm or 86 mm), a drain pan, a jack and jack stands or ramps, and new crush washers for the drain plug. You will also need fresh engine oil in the correct grade and quantity for your model year (typically 5.1 to 6.3 quarts, depending on whether you change the filter at the same time).
The oil filter wrench is essential because the cartridge housing is plastic and can crack if you use a strap wrench or pipe wrench incorrectly. A dedicated cartridge filter wrench grips the flats on the housing without damaging it. You can buy one for $15 to $30, or borrow one from a parts store or friend if you are only doing this once.
Crush washers are small copper or aluminum rings that seal the drain plug. They compress when you tighten the plug and cannot be reused — using the old washer can cause slow leaks. Subaru drain plug kits with new washers cost $3 to $8.
Step-by-step filter replacement process
Start by warming the engine for two to three minutes, then turn it off and let it cool for five minutes. Warm oil drains faster and more completely. Raise the vehicle on a jack and find it with jack stands, or drive it onto ramps. Never work under a vehicle supported only by a jack.
Remove the plastic undertray or splash guard on the driver's side (usually held by clips and a few bolts). Locate the oil filter housing — it is a cylindrical plastic component with a large hex nut on top. Place your drain pan underneath, then use the filter wrench to turn the housing counterclockwise. It will loosen gradually; once it is hand-tight, unscrew it the rest of the way by hand and set it aside to drain.
Unscrew the old filter element from inside the housing and discard it. Wipe the inside of the housing clean with a lint-free cloth. Install the new filter element by hand, turning it clockwise until it seats. Do not force it — hand-tight is correct. Screw the housing back onto the engine, turning clockwise until it is snug, then use the wrench to tighten it an additional three-quarter turn. Over-tightening cracks the plastic.
Replace the crush washer on the drain plug and reinstall the plug, tightening it to 33 foot-pounds (about hand-tight plus a quarter turn with a wrench). Reinstall the undertray, lower the vehicle, and fill the engine with the correct amount of fresh oil. Start the engine, let it run for 30 seconds, then turn it off and wait two minutes. Check the oil level on the dipstick and top up if needed.
How often to replace the filter
Subaru recommends replacing the oil filter every time you change the engine oil. For most Outbacks, that is every 6,000 miles or every six months, whichever comes first. Some newer models with synthetic oil may stretch to 10,000 miles, but check your owner's manual for your specific year and oil type.
Replacing the filter at every oil change ensures you remove accumulated metal particles, dirt, and sludge from the oil. Skipping filter changes between oil changes defeats the purpose of changing oil at all, because the old filter will continue to circulate contaminants through the engine.
Common mistakes to avoid
The most frequent error is over-tightening the plastic housing. Many people assume tighter is better, but the housing threads are plastic and will strip if you crank the wrench too hard. Tighten until snug, then stop — you should be able to unscrew it by hand at the next change.
Another mistake is forgetting the crush washer on the drain plug. Without it, the plug will not seal properly and oil will seep out slowly. Always replace the washer, even if the old one looks fine. A third common error is not warming the engine before draining. Cold oil is thick and drains slowly, leaving more old oil in the pan and reducing the benefit of the change.
Finally, some owners install the filter housing upside down or cross-thread it. The housing has a flat side and a rounded side — the flat side faces up toward the engine. Align it carefully before turning it clockwise, and stop when ready if you feel resistance. Cross-threading will damage the engine block.
When to have a dealer do it instead
If you do not have access to a jack and jack stands, or if you are uncomfortable working under a vehicle, a Subaru dealer or independent shop can replace the filter in 30 to 45 minutes. Dealer labor typically costs $75 to $150 for a filter change alone, plus the cost of the filter and oil. Independent shops often charge less.
You should also have a professional handle it if you notice oil leaking from the housing after your own attempt, or if the housing will not unscrew (it may be stuck due to age or over-tightening by a previous owner). Forcing a stuck housing can crack it, requiring replacement of the entire assembly.
Frequently Asked Questions
Can I use any oil filter, or does it have to be Subaru brand?
You can use quality aftermarket filters that meet Subaru's specifications — look for filters that cross-reference to your model year and engine size. Fram, Bosch, Mobil 1, and Purolator all make compatible filters. Avoid the cheapest no-name filters, as they may have lower filtration efficiency. Genuine Subaru filters are reliable but not required.
What do I do with the old oil and filter?
Take used oil and the old filter to a recycling center, quick-lube shop, or auto parts store — most accept them for free or a small fee. Never pour oil down the drain or into the ground. Many Subaru dealers will also take used oil if you purchase oil from them. Check your local waste management website for drop-off locations near you.
How tight should the housing be when I reinstall it?
Tighten the housing until it is snug by hand, then use the wrench to turn it an additional three-quarter turn. You should still be able to unscrew it by hand at the next change. If you need the wrench to remove it, you over-tightened it. Plastic threads strip easily, so err on the side of loose rather than tight.
Why is my oil filter housing leaking after I replaced it?
The most common cause is a missing or damaged crush washer on the drain plug, or the housing installed cross-threaded or not seated fully. Remove the housing, inspect the threads on both the housing and engine block for damage, and reinstall with a new crush washer. If threads are stripped, the housing or engine block may need professional repair.
Can I change just the filter without changing the oil?
Technically yes, but it defeats the purpose. The filter removes particles from oil, but old oil still accumulates acid, moisture, and sludge over time. Subaru recommends changing both together. If you must change only the filter, do it between full oil changes, but do not skip the full oil change when it is due.