Parts for your 2015 Holden Commodore-Head gasket

2015 Holden Commodore head gasket: what it does, when it fails, and what to do

The 2015 Holden Commodore absolutely uses a head gasket. Technical documentation for the VF Commodore platform confirms this: GM Holden service information for the 3.6L Alloytec SIDI (LFX) V6 and the Gen IV V8s (L77 and late-2015 LS3) specify multi-layer steel (MLS) cylinder head gaskets, head-bolt torque/angle procedures, and replacement during top-end rebuilds. Holden/GM parts catalogues list specific head-gasket part numbers for these engines, and workshop manuals detail the sealing surfaces and torque-to-yield head bolts used with them.

On a 2015 Commodore, the head gasket sits between the engine block and the cylinder head, sealing three critical things at once: high-compression combustion, coolant passages, and oil galleries. The MLS design used in these GM engines copes with heat cycles and head movement better than old composite gaskets, helping reliability across Aussie and Kiwi conditions, from traffic snarls to long country kilometres.

It’s not a routine “service item”, it’s replaced when there’s damage or failure. The best prevention is keeping the cooling system healthy. Use the correct long-life coolant that meets Holden/GM specs, keep the radiator and cap in good nick, and fix overheating promptly. Engines don’t blow head gaskets for fun—heat and detonation are the usual culprits.

Common signs that point to a failing head gasket on a VF Commodore include:

• Unexplained coolant loss or pressurised hoses from cold
• Overheating, heater blowing cold, or bubbles in the overflow
• Milky residue under the oil cap or on the dipstick
• Rough cold start or a persistent misfire
• White exhaust steam once warm, with a sweet smell

If replacement is on the cards, a workshop will typically pressure-test the cooling system, perform a block test for combustion gases, and run compression/leak-down tests. Proper repair means removing the heads, checking flatness, and machining if needed. Always use new head bolts (they’re torque-to-yield), follow the exact torque/angle and sequence from the Holden/GM manual, and fit new intake/exhaust gaskets. It’s also wise to inspect timing chains and guides on the V6 while you’re there, and fit a fresh thermostat and genuine-spec coolant on reassembly. A careful bleed of the cooling system and an oil change round things out. Done right, an MLS gasket on these engines should give years of faithful service.

Popular questions about 2015 Holden Commodore head gaskets

What’s the typical cost to replace a head gasket on a 2015 Commodore in Australia or New Zealand?

Prices vary with engine (V6 vs V8), machining needs, and what’s replaced at the same time. As a ballpark, many owners see a few thousand dollars fitted, with extra if heads need machining, timing items are refreshed, or the cooling system gets new parts. A written quote that lists machining, bolts, fluids, and gaskets is the best way to compare.

Can it be driven with a suspected blown head gasket?

It’s risky. Driving can overheat the engine, wash bearings with coolant, and warp the heads—turning a repair into a full rebuild. If symptoms are present, organise a tow to a trusted workshop for testing. Catching it early usually saves money.

How can owners help prevent head-gasket issues?

Stick to the handbook schedule, use the correct long-life coolant, and don’t ignore temperature spikes. Fix small leaks early, keep the radiator clean and fans working, and run fuel of suitable octane—detonation and heat are the enemies of head gaskets.