The 2005-2009 Legacy with the 3.0L H6 is relatively reliable compared to the 2.5L turbo models, but it's not bulletproof—head gaskets can still fail, transmission oil coolers leak internally destroying the automatic, and front suspension wears quickly. Most catastrophic issues show up after 120,000 miles.
Internal Transmission Oil Cooler Failure (5EAT Auto)
Common · high severityTypical onset: 100,000-150,000 mi
Symptoms: Pink milkshake in coolant overflow—coolant mixing with ATF, Transmission slipping or delayed engagement after overheat, Sudden transmission failure following radiator/cooler leak
Fix: Replace radiator (contains integral oil cooler), flush entire cooling system, drop transmission pan and flush ATF system multiple times. If contamination sat for days, transmission rebuild likely needed—add 12-18 hours labor. Preventive fix: 3-4 hours labor.
Estimated cost: $800-1,200 (radiator/flush only); $3,500-5,500 (if trans rebuild required)
Head Gasket Seepage (External Leak)
Occasional · medium severityTypical onset: 120,000-180,000 mi
Symptoms: Oil seepage at head/block mating surface, visible on lower engine, Coolant smell or small drips, no overheating or combustion leak, May pass for years as minor seep before needing attention
Fix: H6 head gaskets don't catastrophically fail like 2.5L non-turbo, but external seepage happens. Requires engine pull or lifting for access—16-20 hours labor. Replace gaskets, timing components, water pump, and all seals while apart.
Estimated cost: $3,000-4,500
Front Lower Control Arm Bushings and Ball Joints
Common · medium severityTypical onset: 80,000-120,000 mi
Symptoms: Clunking over bumps or during turns, Steering wander or vague on-center feel, Inner front tire wear, alignment won't hold
Fix: Subaru front suspension bushings wear faster than competitors—especially lower control arm rear bushings. Replace control arms as assemblies (bushings alone are difficult to press). 3-4 hours labor for both sides including alignment.
Estimated cost: $800-1,200
Exhaust Y-Pipe and Cat Corrosion
Common · low severityTypical onset: 100,000+ mi (rust-belt areas sooner)
Symptoms: Exhaust leak, loud on cold start, Check engine light—catalyst efficiency codes (P0420/P0430), Visible rust perforation at Y-pipe flex joints or cat shell
Fix: Subaru boxer exhausts run hot and tight to subframe—salt accelerates rot. Y-pipe and cats often need replacement as assembly. 2-3 hours labor, but rusted hardware adds time. Aftermarket options exist.
Estimated cost: $600-1,400 (aftermarket); $1,200-2,000 (OEM)
Ignition Switch Recall and Starter Issues
Occasional · medium severitySymptoms: No-crank no-start, dash lights flicker when key turned, Intermittent starting requiring multiple key turns, Recall for ignition switch spring failure causing no-start
Fix: Check recall status first (NHTSA campaign). If not covered, ignition switch replacement is 1.5 hours; starter replacement (also common on these) is 2-3 hours due to boxer engine layout. Starter often fails from heat soak.
Estimated cost: $300-500 (ignition switch); $500-800 (starter)
Rear Wheel Bearing Noise
Occasional · low severityTypical onset: 90,000-140,000 mi
Symptoms: Humming or growling from rear, louder with speed, Noise changes with turns—louder when load shifts to bad bearing
Fix: AWD system and bearing design lead to earlier wear than expected. Rear wheel bearing hub assembly replacement: 1.5-2 hours per side. Not safety-critical immediately but accelerates if ignored.
Estimated cost: $400-600 per side
Solid choice if transmission oil cooler hasn't grenaded the trans yet and maintenance history is documented—much more durable than the turbo 2.5L, but not as cheap to run as a Camry.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.