The 2008 Impreza with the 2.5L naturally-aspirated EJ253 engine is mechanically simple compared to turbocharged variants, but shares Subaru's notorious head gasket weakness and has some transmission cooling vulnerabilities that can lead to expensive failures if ignored.
External Head Gasket Leaks (EJ253 Engine)
Common · medium severityTypical onset: 80,000-130,000 mi
Symptoms: Oil or coolant seepage visible at cylinder head-to-block junction, Slow coolant loss without visible external puddles, Oily residue on lower engine block near exhaust manifold, Sweet coolant smell after driving
Fix: Replace both head gaskets, resurface heads if warped, new timing components and water pump while apart. 12-16 labor hours depending on condition and whether heads need machine work.
Estimated cost: $2,200-3,500
Transmission Oil Cooler Line Corrosion and Leaks
Common · high severityTypical onset: 90,000-150,000 mi
Symptoms: Red ATF pooling under vehicle near front crossmember, Transmission running hot or erratic shifting, Rust visible on steel cooler lines where they pass through subframe, Low transmission fluid on dipstick despite recent service
Fix: Replace corroded hard lines and rubber hoses from transmission to radiator-mounted cooler. Often combined with radiator replacement if internal ATF-to-coolant contamination suspected. 3-5 hours labor for lines only, 6-8 if radiator included.
Estimated cost: $600-1,200
Piston Ring Land Failure and Oil Consumption
Occasional · high severityTypical onset: 100,000-180,000 mi
Symptoms: Excessive oil consumption (1 quart per 1,000-2,000 miles), Blue smoke on cold start or under acceleration, Carbon buildup on spark plugs, Loss of compression on cylinder #2 or #4 (common pattern)
Fix: Requires short block replacement or full engine rebuild with upgraded piston ring design. Not repairable with top-end work alone. 16-22 labor hours for short block swap with used/reman unit.
Estimated cost: $3,500-6,000
Front Wheel Bearing Failure
Common · medium severityTypical onset: 70,000-110,000 mi
Symptoms: Grinding or humming noise that increases with speed, Noise changes pitch during turns (louder turning one direction), Vibration felt through steering wheel at highway speeds, ABS light intermittent or steady if tone ring damaged
Fix: Replace hub bearing assembly, one side at a time. Simple bolt-on job. 1.5-2 hours per side.
Estimated cost: $300-500
Rear Differential Carrier Bearing Noise
Occasional · medium severityTypical onset: 120,000-180,000 mi
Symptoms: Whining or growling from rear on acceleration or deceleration, Noise pitch changes with vehicle speed, not engine RPM, Metallic shavings visible in differential fluid during service, Noise more pronounced under load (uphill driving)
Fix: Rebuild rear differential with new carrier bearings, pinion bearings, and seals. Sometimes just a fluid change with friction modifier quiets early-stage noise. Full rebuild is 4-6 hours labor.
Estimated cost: $800-1,400
Front Lower Control Arm Bushing Deterioration
Common · low severityTypical onset: 80,000-130,000 mi
Symptoms: Clunking over bumps at low speed, Steering feels vague or wandering on highway, Uneven inner tire wear, Visible cracking or separation of rubber bushings during inspection
Fix: Replace control arms as complete assemblies (bushings not serviceable separately on this generation). 2-3 hours for both sides, includes alignment.
Estimated cost: $500-800
Ignition Switch Electrical Failure (Recall-Related)
Rare · high severitySymptoms: Intermittent no-start, no crank condition, Dash lights flicker when key turned, Accessories work but starter does not engage, Engine shuts off while driving in extreme cases
Fix: Replace ignition switch assembly in steering column. Check if recall 15V-342 was completed; if not, dealer handles free. DIY is 1.5-2 hours with steering column disassembly.
Estimated cost: $200-400
Buy it if the head gaskets have been done and oil consumption is under control, but budget $3k-5k for deferred powertrain work if purchasing high-mileage—solid chassis and AWD system make it worthwhile if the engine isn't already damaged.
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.