Parts for your 2009 Subaru Forester-Oil seals

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

Based on the Subaru Factory Service Manual for the 2009 Forester (SH, EJ25) — Engine Lubrication, Timing Belt, and Transmission sections — and the Subaru FAST electronic parts catalogue, this model is fitted with multiple oil seals from factory. Those documents list items such as crankshaft oil seals (front and rear), camshaft oil seals, oil pump seal, front transaxle/differential side oil seals, and rear differential pinion and side oil seals. So yes, oil seals are absolutely relevant to the 2009 Subaru Forester.

Oil seals are small but vital. They keep engine and driveline oils in, and dust, water, and grit out. On the Forester, they’re radial-lip seals designed to run on rotating shafts — think crankshaft, camshafts and diff stubs — usually made from high-temp elastomers to handle Aussie and Kiwi conditions.

Common oil seals on a 2009 Forester include:

• Engine: front crankshaft seal, rear main (crank) seal, camshaft seals, oil pump seal
• Driveline: front transaxle/diff side seals, transfer case output seal (auto), rear diff pinion and side seals

As part of routine servicing, a quick once-over for dampness or weeping goes a long way. Tell-tales are oil mist at the lower timing cover (front crank/cam), oil at the bellhousing join (rear main), or wetness around axle stubs (front diff/auto), plus drips under the rear diff. Burning oil smells after a drive can also point to a leak onto hot exhaust bits.

There’s no hard “replace by” interval, but many owners choose to renew the front crank and cam seals proactively when doing the timing belt (around 100,000 km or on age, per market guidance in the FSM). It’s smart, cost-effective, and saves double handling. Rear main seals are usually done when the gearbox is out (clutch on manuals, trans work on autos). Axle and diff seals are replaced when leakage is present or when shafts are out for other work.

Good practice from the service literature: use quality OEM-spec seals, check the crankcase ventilation (a tired PCV system can push seals out), inspect shaft surfaces for grooves, install to the specified depth with a proper driver, lightly oil the lip, and torque pulleys/fasteners to FSM specs. That keeps the Forester tidy under the bonnet and the driveway free of spots.

Popular questions about 2009 Subaru Forester oil seals

How often should oil seals be replaced on a 2009 Forester?
There’s no strict interval. Inspect at every service. Many techs replace the front crank and cam seals during the timing belt job (about 100,000 km or by age) if there’s any weeping. Rear main, axle and diff seals are done when signs of leakage appear or when related components are already being removed.

What are the common leak spots on this model?
Front crank/cam seals can mist oil onto the timing cover, rear main can show at the bellhousing join, front transaxle side seals may wet the inner CV areas, and rear diffs can sweat at the pinion or side seals. A clean engine and regular checks make small leaks easy to spot before they become messy.

Can a home mechanic replace these seals?
Some, yes — axle and diff side seals are moderate jobs. Front crank and cam seals require timing belt removal and correct alignment, so they’re best tackled by a confident DIYer with the right tools or a trusted workshop. Rear main typically needs the gearbox out, so most owners leave that to a pro.