Parts for your 2006 Subaru Forester-Oil seals

2006 Subaru Forester oil-seals — what they do and when to sort them

Oil-seals absolutely are used on the 2006 Subaru Forester (SG series). The Subaru Factory Service Manual for 2006MY Forester (engine mechanism and drivetrain sections) and the Subaru FAST parts catalogue both detail crankshaft front and rear oil-seals, camshaft seals, oil pump sealing, and differential/output shaft oil-seals for the EJ-series engines and AWD driveline fitted to this model. These are standard service parts designed to keep fluids where they belong.

On this Forester, oil-seals do the everyday graft of holding engine oil inside the rotating assemblies and keeping grime out. They sit where shafts spin through housings, using a spring-loaded lip against a machined surface to maintain a tidy, leak-free film of oil. When they harden or wear, oil seeps out, making a mess under the bonnet or on the driveway, and can lead to low oil levels if ignored.

Common seal locations on a 2006 Forester include:

• Engine: front crankshaft seal (behind the timing cover), rear main seal (between engine and gearbox), camshaft seals, and oil pump seal/O-ring.
• AWD driveline: front differential/output shaft seals, driveshaft and rear differential axle seals.

For servicing, it’s smart to treat seals as “do it once, do it right” items. During a timing belt job (around the 100,000 km mark for many AU/NZ schedules), it’s sensible to inspect and proactively replace the front crank and cam seals while access is easy. That little bit of extra parts cost can save paying for the same labour twice. If the Forester’s a manual and the clutch is coming out, that’s the perfect time to replace the rear main seal, as the gearbox has to be removed anyway.

Tell-tale signs that oil-seals need attention include dampness around the timing cover, oil mist on the undertray, a whiff of burning oil after a drive, or an oily bellhousing (rear main). Keeping the PCV system healthy matters too, excess crankcase pressure can force fresh seals to leak. For longevity, use genuine Subaru seals or quality Viton equivalents, lubricate the seal lip on installation, and check the shaft surface for grooves. After fitting, recheck for weeps at the next service and keep an eye on oil level between visits.

Quick tips:

• Pair seal replacement with related jobs (timing belt, clutch) to save labour.
• Clean mating surfaces, seat seals square, and avoid driving them in too deep.
• If leaks return quickly, pressure-test the PCV and inspect breather hoses.

Which oil-seals should be replaced with the timing belt on a 2006 Forester?

The front crankshaft seal and both camshaft seals are the usual picks while the timing belt is off. Access is already sorted, so it’s a tidy, cost-effective add-on. Many workshops also refresh the oil pump O-ring if there’s any sign of sweating, and replace the belt, tensioner and idlers as a package for reliability.

How can someone tell if the rear main seal is leaking on a Forester?

Look for fresh oil at the bellhousing weep hole or the lower edge of the gearbox, plus oil on the clutch dust if it’s a manual. It can mimic a rocker cover leak, so a proper clean and recheck is wise. Because the gearbox needs to come out, most owners tackle the rear main when doing a clutch or if the leak is more than a light weep.

What causes repeated oil-seal leaks on EJ engines?

Common culprits are a blocked or weak PCV system building crankcase pressure, a worn shaft sealing surface, incorrect seal seating depth, or cheap seal material that hardens with heat. Sorting the breather/PCV setup and using quality seals, fitted square and lubricated, usually stops the merry-go-round.