2021 Subaru Forester maintenance schedule
The 2021 Forester is part of the SK generation (2019-2024), sold as an SUV. Below: its service intervals with the source behind each one, the fluids it takes, the problems owners report for this year, and the NHTSA recalls issued for it.
Service schedule
What the 2021 Forester needs, and when
5 of these 12 items come from Subaru's own published schedule. Manufacturer rows link to Subaru's own schedule, Independent rows to a service shop or parts retailer's published guide.
| Service | Interval | Source |
|---|---|---|
| Engine oil and filter (FB25) Heavy usage dictates 3,000-mile intervals. | 6,000 mi / 6 months | Manufacturer |
| Engine air filter (FB25) Replace regularly; 7,500 miles for heavy/dusty use. | 30,000 mi / 30 months | Independent |
| Cabin air filter (FB25) | 12,000 mi / 1 year | Independent |
| Tire rotation (FB25) Inspect and rotate | 6,000 mi / 6 months | Independent |
| Brake fluid (FB25) Flush system | 30,000 mi / 30 months | Manufacturer |
| Engine coolant (FB25) Initial change at 11 years, then every 75k miles/6 years using Subaru Super Coolant. | 137,500 mi / 11 years | Manufacturer |
| Transmission fluid (FB25) Inspect fluid; severe service dictates replacement sooner. | Inspect, replace as needed | Manufacturer |
| Spark plugs (FB25) | 60,000 mi / 5 years | Manufacturer |
| Serpentine belt (FB25) Inspect drive belt(s) | Inspect, replace as needed | Independent |
| Differential and transfer case fluid (FB25) | Inspect, replace as needed | Independent |
| PCV valve (FB25) Check PCV valve | Inspect, replace as needed | Independent |
| 12V battery (FB25) Test / replace. | 30,000 mi / 3 years | Independent |
Intervals are for normal driving; towing, short trips, extreme heat or dust shorten them.
Fluids and engines
What goes in it
- Coolant
- Subaru Super Coolant
- Transmission fluid
- CVT Fluid
Powertrains in this generation
- 2.5L 4-cyl (FB25), CVT, AWD
Confirm the exact spec against the owner's manual or the label under the hood; capacities vary by engine and drivetrain.
Known problems
What 2021 Forester owners run into
Problems reported for this model year, with the mileage they tend to show up at. Buying past a window is not automatically a pass - it just needs to be priced in.
Thermo Control Valve
high severityFrom about 50,000 mi · $1,000-$1,500 to fix
Overheating, poor heater performance, CEL P26A3/P26A5
Source: youtube.com
12V Battery Drain
medium severityFrom about 10,000 mi · $200-$400 to fix
Starting battery goes flat after 5-10 days of inactivity
Fragile Windshield
medium severityFrom about 10,000 mi · $700-$1,200 to fix
Spontaneous cracking requiring expensive acoustic glass
Intake Carbon Buildup
medium severityFrom about 50,000 mi · $400-$1,200 to fix
Rough idle, random misfires (P0300)
Source: au7o.io
Safety recalls
No NHTSA recalls matched the 2021 Subaru Forester
From NHTSA's recall database, matched by model and year. Recall repairs are free at Subaru dealers, and a given car may already be fixed or fall outside a campaign, so check the VIN at nhtsa.gov/recalls before you buy.
Running costs
What maintenance typically costs
- A typical year of maintenance
- $632
Typical US independent-shop estimates for this generation; they vary by region and condition.
Other Forester model years
Shopping new? The Subaru Forester guide covers the current model, with what it costs to keep for 1 to 15 years.
Sources
- techinfo.subaru.com (Manufacturer)
- autonationsubaruarapahoe.com (Independent)
- youtube.com (Owner forum)
- au7o.io (Unverified)
Researched 2026-09-21. Modeling, not mechanic advice - always confirm against your car's owner's manual and service records.
Running a Forester for income?
Carlyle scores the exact listing on cost per remaining mile and projected Turo income, so you know what a 2021 Forester earns before you buy it.
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