Free repair checklist
Change Your Forester's Oil — FA24F and FB25 Both Covered
The 2020 Subaru Forester uses either the FA24F (2.5L turbo) or FB25 (2.5L naturally aspirated) — both take 5.1 qt of 0W-20 full synthetic, but cold-start oil dilution is a known issue on both engines. This free guide covers the correct spec, the dilution warning, and the steps to do it right at home.
This checklist is a practical starting point. The DIY Mechanic System gives you a clearer path to diagnose the problem, plan the job, and complete the repair.
What this checklist covers
- 5.1 qt 0W-20 full synthetic — the exact spec for both the FA24F and FB25 engines in the 2020 Forester
- Cold-start oil dilution warning — a known Subaru issue that makes using the correct grade critical
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