Parts for your 2009 Subaru Legacy-Oil seals

2009 Subaru Legacy oil seals — what they do and when to replace them

Oil seals are absolutely used on the 2009 Subaru Legacy. This isn’t guesswork: the Subaru Factory Service Manual for the 2009 Legacy/Outback (BP/BL) and Subaru’s ANZ parts catalogue specify multiple oil seals throughout the engine, transmission and differentials. These include the front and rear crankshaft oil seals, camshaft oil seals, transmission input/output and selector seals, front differential/axle side seals, and rear differential pinion and side seals. If a 2009 Legacy has petrol and rotating shafts, it’s got oil seals keeping the fluids where they belong.

The purpose of these seals is simple but critical: keep engine or gear oil in, keep dust and water out, and maintain stable oil pressure. On the EJ-series 2.5-litre engines fitted to 2009 models, the crankshaft and camshaft seals ride on spinning shafts under the timing covers, while the gearbox and diffs use lip seals around axle stubs and shafts. When they harden or wear, owners see weeping around the timing covers, oil mist under the bonnet, a burning-oil whiff on hot days, or oily residue at the bellhousing or axle flanges.

• Common engine seals on this model: front crankshaft seal, rear main seal, and both camshaft seals.
• Driveline seals: manual and auto transmission input/output and selector seals, front diff/axle side seals, rear diff pinion and side seals.

Best practice is to replace the front crank and both camshaft seals during a timing belt service, as access is already open. Depending on market schedule, that’s typically around 100,000–160,000 kilometres or at the major belt interval. If oil has contacted the timing belt, replace the belt as well. For gearbox and diff seals, replace at the first sign of leakage and top up or renew the appropriate gear oil afterwards.

Good workshop habits help these seals live longer: ensure the PCV system isn’t blocked (excess crankcase pressure will push oil past good seals), inspect for nicks on the shaft sealing surfaces, and drive new seals square using the correct installer. Most Subaru lip seals are installed lightly oiled on the inner lip