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2021 Subaru Forester Maintenance Schedule
- Generation
- SK (5th generation, 2019–present)
- Engine
- 2.5L DOHC naturally aspirated (182 hp)
- Intervals
- 13
The 2021 Subaru Forester pairs a horizontally-opposed boxer engine with standard AWD and a CVT transmission, both of which require specific maintenance attention to prevent costly repairs. This schedule covers all factory-recommended intervals and is essential for owners who want to preserve reliability and resale value.
Service Intervals
Where is your Forester right now?
Type the odometer and the table below re-sorts by what's closest. It works from the reading alone — it can't see what you've already had done.
Est. costs are US-typical, in USD.
| Service | Interval | Est. Cost |
|---|---|---|
| Engine Oil & FilterSafety itemSubaru recommends 6,000-mile intervals for the naturally aspirated engine; use 0W-20 synthetic oil to protect the boxer engine and CVT. | 6,000 mi / 6 mo | $35–$75 |
| Tire RotationRotate all four tires every 7,500 miles to ensure even wear on the standard AWD system. | 7,500 mi | $20–$50 |
| Engine Air Filter ReplacementReplace the engine air filter every 30,000 miles or sooner if driving in dusty conditions; a clogged filter reduces fuel economy and engine performance. | 30,000 mi | $30–$60 |
| Cabin Air Filter ReplacementReplace the cabin air filter every 15,000 miles to maintain HVAC performance and interior air quality. | 15,000 mi | $25–$50 |
| Brake Fluid Inspection & FlushSafety itemSubaru specifies brake fluid replacement every 2 years regardless of mileage to prevent moisture absorption and brake system corrosion. | 24 mo | $100–$200 |
| Brake Pads & Rotor InspectionSafety itemInspect brake pads and rotors at 30,000 miles; replacement intervals vary by driving style but typically occur between 30,000–70,000 miles. | 30,000 mi | $150–$400 |
| CVT Fluid Inspection & ReplacementSafety itemThe CVT is the Forester's most vulnerable component; Subaru recommends inspection at 60,000 miles and replacement every 60,000–100,000 miles depending on driving conditions. | 60,000 mi | $150–$250 |
| Engine Coolant Flush & ReplacementReplace coolant every 105,000 miles or 10 years; use Subaru-approved coolant to prevent corrosion in the aluminum boxer engine. | 105,000 mi | $100–$180 |
| Spark Plugs ReplacementReplace spark plugs every 60,000 miles on the 2.5L naturally aspirated engine to maintain fuel economy and ignition reliability. | 60,000 mi | $100–$200 |
| Transmission Fluid Check (CVT)Safety itemCheck CVT fluid color and level every 30,000 miles; dark or burnt-smelling fluid indicates overheating and requires immediate service. | 30,000 mi | $0–$30 |
| All-Wheel Drive System InspectionInspect AWD coupling and differentials every 60,000 miles; the Forester's standard AWD system is durable but benefits from regular checks. | 60,000 mi | $50–$100 |
| Battery Inspection & ReplacementInspect battery health every 3 years; most OEM batteries last 3–5 years in the Forester's climate-controlled engine bay. | 36 mo | $100–$200 |
| Suspension & Steering InspectionInspect struts, control arms, and tie rods every 60,000 miles; the Forester's independent suspension is robust but benefits from regular wear checks. | 60,000 mi | $75–$150 |
2021 Subaru Forester Oil Change Interval
The 2021 Subaru Forester oil change interval is every 6,000 mi or 6 months, whichever comes first (estimated cost $35–$75). Subaru recommends 6,000-mile intervals for the naturally aspirated engine; use 0W-20 synthetic oil to protect the boxer engine and CVT.
What Happens If You Skip It
- Skipping CVT fluid service is the leading cause of transmission failure in Foresters; repairs exceed $3,000–$5,000 and often result in total replacement.
- Neglecting brake fluid flushes allows moisture to corrode the ABS module and brake lines, leading to brake failure or expensive ABS repairs ($800+).
- Ignoring spark plug replacement at 60,000 miles causes misfires, reduced fuel economy, and potential catalytic converter damage.
- Delaying coolant replacement accelerates corrosion of the aluminum cylinder head and water pump, increasing long-term wear on cooling system components.
- Skipping tire rotations on the AWD system causes uneven wear and premature differential stress, potentially requiring $1,500+ differential service.
- Neglecting cabin air filter replacement reduces HVAC efficiency and can allow moisture into the blower motor, causing mold and electrical failures.
Common Issues at Higher Mileage — 2021 Subaru Forester
CVT shuddering, hesitation, or overheating; fluid degradation is the primary cause and requires fluid replacement or transmission rebuild.
Brake pad wear sensors failing or brake fluid contamination causing ABS light activation; fluid flush and sensor replacement needed.
Strut mount bearing wear causing clunking noises over bumps; suspension refresh ($600–$1,200) extends vehicle life.
Minor oil seepage from valve cover or cam seals can occur with age; head gasket failure, a known issue on older SOHC EJ25 engines, is rare on the FB25 DOHC engine used in the 2021 Forester.
Common questions about the 2021 Subaru Forester
How often does a 2021 Subaru Forester need an oil change?
The 2021 Subaru Forester oil change interval is every 6,000 mi or 6 months, whichever comes first (estimated cost $35–$75). Subaru recommends 6,000-mile intervals for the naturally aspirated engine; use 0W-20 synthetic oil to protect the boxer engine and CVT.
What maintenance does a 2021 Subaru Forester need?
The services not to skip on a 2021 Subaru Forester: engine oil & filter every 6,000 mi / 6 mo; brake fluid inspection & flush every 24 mo; brake pads & rotor inspection every 30,000 mi; cvt fluid inspection & replacement every 60,000 mi; transmission fluid check (cvt) every 30,000 mi. The table above lists every service with its interval and an estimated cost.
What goes wrong on a Subaru Forester at higher mileage?
What owners report as the miles add up — 80,000+ mi: CVT shuddering, hesitation, or overheating; fluid degradation is the primary cause and requires fluid replacement or transmission rebuild. 90,000+ mi: Brake pad wear sensors failing or brake fluid contamination causing ABS light activation; fluid flush and sensor replacement needed. 100,000+ mi: Strut mount bearing wear causing clunking noises over bumps; suspension refresh ($600–$1,200) extends vehicle life. 100,000+ mi: Minor oil seepage from valve cover or cam seals can occur with age; head gasket failure, a known issue on older SOHC EJ25 engines, is rare on the FB25 DOHC engine used in the 2021 Forester.
