Subaru Legacy BT

Subaru's volume boxer: 2.5L NA in Legacy, Outback, Forester. Oil consumption class action for 2011-2014 models — piston rings didn't seat properly. Cam carrier seal leaks from ~60k miles (labor-intensive). Thermo control valve on 2019-2022 models: plastic housing fails under heat — Subaru extended warranty to 15 years. Improved from 2023.

• !! Oil Consumption — Piston Rings (2011-2014) from 40,000 km

  Class action for 2011-2014 Forester, Legacy, Outback. Piston rings didn't seat due to variable bore roughness. Worst cases: 1 quart per 800 miles.

  Symptoms: Extreme oil consumption, frequent top-ups needed, blue smoke possible
  4,000–6,000 $
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• !! Cam Carrier Seal Leak from 100,000 km

  Known FB engine problem: seal between cam carrier and cylinder head fails. Labor-intensive due to poor access. Service bulletins published.

  Symptoms: Oil stain under engine, oil smell while driving, visible oil seepage at cylinder head
  1,700–6,000 $
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• !! Thermo Control Valve Failure (2019-2022) from 60,000 km

  Electronic TCV plastic housing fails above 200°F. All warning lights simultaneously (EyeSight, front collision). Warranty extended to 15 years/150k miles. Mechanical thermostat replaces TCV from 2023.

  Symptoms: All warning lights at once, no heater, fault codes P2682/P26A3/P26A5
  1,300–1,800 $
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+ 1 more engine weaknesses + vehicle weaknesses

Subaru's newest and best turbo boxer: 2.4L direct injection, used in WRX VB, Ascent and Outback XT. Oil pan RTV sealant was the early issue (fixed under warranty, corrected from 2025). Too early for real long-term data, but Ascent owners past 100k miles report trouble-free operation. Budget for carbon buildup cleaning like all DI engines.

• !! Recall: PCV Valve Separation (WUW-08)

  Recall WUW-08 (Dec 2019): ~51,600 vehicles. Steel washer in PCV valve separates due to heat cycling — engine oil and fragments enter combustion chamber. Engine loses drive power. Free repair; short block replaced if valve fragments not found.

  0–0 $
• !! Thermo Control Valve Failure (2019-2021) from 60,000 km

  Plastic thermo control valve (TCV) housing fails under heat cycling. Coolant vapor short-circuits sensor reference line — all driver assist systems go offline. Warranty extended to 15 years/150,000 miles. Affects 2019-2021.

  Symptoms: All warning lights simultaneously, vehicle becomes inoperable, disabled safety systems (EyeSight, lane keep), engine overheating
  800–1,200 $
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• ! Oil Pan RTV Sealant Leak from 30,000 km

  Sub-optimal factory RTV application at the oil pan. Service bulletin published, repaired under warranty. Corrected at the factory from 2025.

  Symptoms: Oil drops under engine, oil level loss
  400–500 $
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+ 2 more engine weaknesses + vehicle weaknesses