Subaru Tribeca B9

Six-cylinder boxer: 3.6L naturally aspirated, smooth and torquey. Significantly more reliable than the EJ four-cylinders. Oil leaks at valve covers and timing chain cover at higher mileage are the main concerns. No head gasket issues. 200k+ mile lifespan realistic.

• !! 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
  1,500–3,200 $
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• ! 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
  800–2,000 $
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• ! Serpentine Belt Tensioner Worn from 130,000 km

  Belt tensioner spring fatigues after approximately 75,000-95,000 miles. Loss of tension causes slipping, squealing, and in severe cases, failure of the alternator and A/C compressor.

  Symptoms: Squealing from engine bay, A/C failure, battery warning light, overheating
  250–400 $
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