Subaru Legacy BN
Weaknesses, engine ratings and buying advice
The Legacy BN (2015-2019) is the sixth-generation US-market sedan — Subaru never sold this one in Europe. It's the everyman Subaru: symmetrical AWD standard, roomy, frugal, dead simple. Buyers are commuters and snow-belt families who want all-wheel drive without paying SUV money. Don't expect excitement; expect dependability.
Engines are a two-horse race plus a six. The base FB25 2.5 naturally aspirated four is the volume seller — torquey enough, reasonably efficient, and proven. It can sip oil with age, so watch the dipstick, but it's a buy-with-confidence block when serviced. The EZ36 3.6R flat-six (3.6R trim) is the smooth, gutsy choice for highway miles; it never had the head-gasket reputation of the old EJ sixes. There's no engine to truly avoid here — the risk is the transmission, not the motor.
The big-ticket worry is the CVT (Lineartronic). Owners report shudder, hesitation and a back-and-forth wobble as it ages, and in bad cases enough hesitation to nearly stall. A replacement runs $3,000-$5,000, so a smooth, judder-free test drive is non-negotiable. Wheel bearings fail early — a Subaru signature — humming from the rear around 70,000-100,000 miles, roughly $300-$500 a corner. The Denso low-pressure fuel pump recall hit these years: the impeller can deform and cause sudden stalling — verify it's been performed. EyeSight has a class-action history of false pre-collision braking; confirm software updates. And the acoustic-windshield class action covers spontaneous cracking on these cars.
Test-drive red flags: any CVT shudder, hesitation off the line, or rpm flare; humming from the rear (bearings); a check-engine or fuel-pump warning; phantom EyeSight braking events; and a cracked or recently replaced windshield (ask why).
2026 used pricing: clean BN sedans run roughly $8,000-$15,000 depending on year, mileage and trim; low-mile 2018-2019 3.6R Limited cars sit at the top.
Insider pick: a well-kept 3.6R Limited with documented CVT service and the Denso pump recall closed out. The six is the sweet spot — smoother, no oil-consumption nag, and it makes the heavy sedan feel effortless. If budget is tight, a serviced FB25 is fine, just insist on a flawless CVT.
Generations
Engine Overview
The Subaru Legacy BN is available with 2 engine variants — from 167 to 260 hp.
The 2.5-litre NA petrol boxer with a timing chain uses port or direct injection depending on the year. At 125–134 kW it gives enough torque for the mid-size models and is fundamentally solid. The early 2011–2014 builds are affected by the known oil-consumption issue (piston rings, settled by a US class action). Across the years a cam-carrier oil leak appears, whose repair needs the engine out and can run into four figures. The direct-injection units from 2019 tend to coke the valves and have a fragile electronic thermo-control valve whose cracking plastic housing can cause overheating — here too the maker extended the warranty significantly. Otherwise a reliable daily engine with no timing-belt service.
- !! Thermo Control Valve Failure (2019-2022) from 60,000 km
The direct-injection engines' electronic thermo-control valve (from 2019) has a plastic housing that cracks; coolant vapour destroys the internal electronics. Stuck closed, the engine overheats within minutes. Subaru extended the warranty to 15 years/150,000 miles (part 21319AA010 → 21319AA040).
Symptoms: Check-engine light with codes P0128/P0125/P26Ax, no or delayed heater warmth, fluctuating coolant temperature, in severe cases sudden overheating. - !! 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 - !! 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 more engine weaknesses + vehicle weaknesses
The 3.6-litre flat-six is one of Subaru's most reliable designs and is considered much more durable than the smaller H6 predecessor. Mileages beyond 300,000 km are not rare on cared-for examples. The timing chain is designed for engine life; only the plastic tensioner can develop play at high age. The most common issue is oil leaks: the timing-chain cover is sealed with liquid sealant rather than a gasket, which dries out after many years — a correct reseal is involved and often needs the engine out. The serpentine-belt tensioner also wears over time. Otherwise there are no design weak points. Regular oil changes and checking for damp seals low at the front are important.
- !! Timing Chain Tensioner Worn from 150,000 km
Plastic timing chain tensioner wears after 90,000+ miles and can no longer maintain adequate chain tension. Starts with cold-start rattle, can progress to timing chain jump. Expensive repair due to many bolts on the chain cover.
Symptoms: Rattling on cold start, loud chain noise, misfires at high mileage - !! Timing-cover oil leak from 160,000 km
The aluminium timing-chain cover is sealed not with a gasket but with liquid sealant. Over time it dries out and the engine seeps oil at the seams, later dripping. A correct reseal often needs the engine out.
Symptoms: Oil marks on the ground, an oil smell in the bay, seeping seams low on the timing cover, a slowly dropping oil level. - ! Oil Leaks at High Mileage from 120,000 km
Valve cover gaskets and timing chain cover become leaky at higher mileage. Typical for boxer engines with many sealing surfaces. Not a critical weakness, but noticeable cosmetically and by smell.
Symptoms: Oil spots under engine, oil smell when engine is hot
+ 1 more engine weaknesses + vehicle weaknesses
Vehicle Weaknesses
| Weakness | Cost | |
|---|---|---|
| CVT Judder (Lineartronic) Revised Lineartronic CVT — significantly more reliable than BM, but neglected fluid maintenance leads to judder. Warranty extended to 10 years/100,000 miles. Symptoms: Juddering on light throttle takeoff, delayed response, engine revving from 100,000 km | High |
Top Reported Issues
Alternatives
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Known Problems and Issues +
A total of 13 weaknesses have been documented for the Subaru Legacy BN (2015–2019) — 8 engine-related and 5 vehicle-related. One problem engine: FB25 (2.5L NA). Typical issues affect Gearbox, Suspension, Electronics, Other. Considered reliable: EZ36 (3.6L H6).
Legacy (FB25, 2015–2019) — Stay Away!: Thermo Control Valve Failure (2019-2022), Oil Consumption — Piston Rings (2011-2014), Cam Carrier Seal Leak. Power: 173 PS.
What to watch out for with the Subaru Legacy? See the detailed listing of all engine and vehicle weaknesses in the sections above.
Frequently Asked Questions
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Last updated: February 2026 · All information without guarantee