Parts for your 2009 Subaru Legacy-Exhaust gasket

2009 Subaru Legacy Exhaust Gasket

Technical documentation confirms the 2009 Subaru Legacy does use exhaust gaskets. The Subaru Factory Service Manual for the BP/BL Legacy (Exhaust section) and the Subaru Genuine Parts Catalogue list multiple gaskets, including the exhaust manifold-to-cylinder head gasket and the front pipe “donut” gasket at the spring-joint, with commonly referenced Subaru part numbers such as 44022AA123 (manifold gasket) and 44011AA170 (pipe donut), varying by engine variant. Therefore, an exhaust gasket is absolutely relevant to this model.

The exhaust gasket on a 2009 Subaru Legacy keeps the system sealed from the cylinder head all the way back to the mufflers. Its job is simple but critical: stop hot gases and noise escaping at the flanges, protect the oxygen sensors and cat from false readings or overheating, and keep the car nice and quiet so it meets Aussie and Kiwi road rules without drama.

When it’s time for servicing, the exhaust gaskets deserve a look. There’s no strict replacement interval, they’re changed when disturbed or if they show signs of leaking. Common clues are a ticking sound on cold start that quietens as it warms up, a whiff of exhaust under the bonnet or near the floor, faint soot marks around flanges, or a raspier note from the tail. On an AWD Legacy that sees plenty of wet roads, corrosion on hardware and flanges can accelerate wear.

Best practice during any exhaust work is to fit new gaskets rather than reusing old ones—especially the crush-style donut at the spring joint and flat ring gaskets at the mid-pipe or mufflers. For manifold gaskets, fresh OEM-quality multi-layer steel items are the safe bet if the manifold’s been off. Clean the mating faces, check flange flatness, replace tired springs and studs, and tighten fasteners evenly to the factory spec from the service manual. After a couple of heat cycles, a quick recheck of fasteners helps keep things sealed.

Choosing quality parts matters. Genuine Subaru or equivalent high-temp, graphite-coated or MLS gaskets tend to last longer and seal better. If the exhaust is coming off for a clutch, O2 sensor, or cat job, budget for new gaskets and hardware—it’s small money that saves repeat visits and annoying leaks. For WOF/regos and a quieter, smoother Legacy, a sound gasket seal is the go.

• Replace gaskets whenever a joint is separated.
• Inspect for soot tracks, noise, or odour at every service.
• Use correct hardware (springs, bolts, studs) and follow the FSM torque guidance.

Popular questions

Which exhaust gaskets does a 2009 Subaru Legacy use?
This model typically uses an exhaust manifold-to-head gasket and one or more pipe-to-pipe gaskets, including a spring-joint donut at the front pipe and flat or ring gaskets further back. Common Subaru references include 44022AA123 (manifold) and 44011AA170 (donut), but exact parts vary with engine (EJ253 vs EZ30) and trim. Checking by VIN against the parts catalogue is the tidy way to nail it.

Can exhaust gaskets be reused on a 2009 Legacy?
Not recommended. Crush-style and donut gaskets are one-time use. Even if an MLS manifold gasket looks tidy, replacing it when the manifold’s off helps avoid leaks that can trip O2 readings or make the car too loud. Fresh hardware and gaskets are cheap insurance.

What are the signs of a leaking exhaust gasket?
Expect a ticking noise on cold start, faint fumes under the bonnet or near the floor, sooty marks at the joint, or a sharper exhaust note. Some drivers also notice a slight loss of low-end torque. If any of these pop up, a gasket inspection is on the cards.