Parts for your 2015 Holden Commodore-Manifold gasket

2015 Holden Commodore manifold gasket — fitment, purpose and service advice

Yes, a manifold gasket is used on the 2015 Holden Commodore. Technical sources including the Holden/GM Service Information (VF Commodore workshop procedures), the Holden Electronic Parts Catalogue (EPC), and AC Delco/Permaseal parts listings all specify intake manifold gaskets and exhaust manifold gaskets for the VF range engines (3.0L SIDI V6, 3.6L LFX V6, 6.0L L77 V8 and late-2015 6.2L LS3 V8). The factory service manual details removal/installation steps that require inspection or replacement of these gaskets, confirming they’re fitted from the factory.

On the VF Commodore, the manifold gasket’s job is straightforward but critical: it seals the junctions where the intake manifold meets the cylinder heads (keeping unmetered air out and fuel/air flow accurate) and where the exhaust manifold meets the heads (keeping hot exhaust gases in the system for proper scavenging and emissions control). Proper sealing preserves smooth idle, stable fuel trims, power, economy, and prevents exhaust noise and under‑bonnet heat issues.

Intake manifold gaskets on the V6 and V8 models are typically moulded rubber or composite designs that sit in grooves on the manifold, exhaust manifold gaskets are multi‑layer steel or graphite/steel laminates made to handle thermal cycling. When these age or are disturbed during other repairs, they can leak.

Tell‑tale signs include:

• Intake side: rough idle, a whistling/vacuum leak noise, lean fuel trims, engine light (P0171/P0174 type codes), and poor cold starts.
• Exhaust side: ticking on cold start that softens warm, exhaust smell in the engine bay, sooty marks near the flange, and possible O2 sensor/efficiency codes.

While there’s no set replacement interval, the gasket is commonly renewed any time the manifold is removed. For a tidy job, follow GM SI procedures: disconnect battery, label hoses/looms, remove the manifold, clean mating faces without gouging, and fit new gaskets dry unless the manual calls for a dab of sealant at specific joints. Use a torque wrench and the specified sequence, some engines require new exhaust manifold bolts or studs—check the parts notes in the EPC or AC Delco listings.

Good preventative care includes fixing misfires promptly (raw fuel and heat are tough on exhaust gaskets), keeping PCV/breather systems clear, and replacing brittle vacuum hoses that can mimic intake gasket leaks. If there’s exhaust ticking or a persistent lean condition, don’t leave it—small leaks often become big, and that can toast nearby components.

Popular questions about the 2015 Holden Commodore manifold gasket

How can someone tell if the intake manifold gasket is leaking on a VF Commodore?
They’ll usually hear a faint hiss and notice a lumpy idle, especially when cold. A scan tool often shows positive long‑term fuel trims. Spraying a little soapy water or safe intake cleaner near the gasket area at idle can change engine speed if there’s a vacuum leak. Any coolant smell or staining on models where coolant runs through the manifold area is another clue.

Is it okay to keep driving with a leaking exhaust manifold gasket?
It’ll usually still drive, but it’s not recommended. Hot gases can damage wiring and nearby plastics, and the leak can skew O2 sensor readings. That ticking can also turn into a warped flange or broken stud if ignored, which makes the repair costlier.

Do manifold gaskets need sealant when installing?
Generally no. The OEM gaskets are designed to seal dry. Only apply sealant where the Holden/GM procedure explicitly calls for it—typically at timing cover-to-block corners or joint steps, not across the gasket faces. Over‑sealing can cause squeeze‑out and future leaks.