Considering an LPG Conversion?

What is LPG fuel?

Liquefied petroleum gas, or LPG, is a hydrocarbon fuel used in heating appliances and vehicles. LPG is available in mixes that are mainly propane, butane or both. Take note that the LPG used in cooking barbecues is different from the automotive LPG, which is otherwise known as autogas.

Automotive LPG is said to be used as an eco-friendly fuel because it reduces carbon dioxide emissions by roughly 35 per cent compared to petrol. It has an octane rating from 90 to 110 and energy content between 25 to 28 megajoules per litre, depending on the composition.

Why you should consider LPG

You should seriously consider switching to LPG because of its major cost savings. Autogas is worth around half the price of unleaded petrol. The advantages don’t end there: LPG reduces carbon dioxide emissions and can extend your car engine’s lifespan.

Cost of LPG conversion

LPG conversions would generally cost you around AUD3,000 to AUD4,500. Since LPG injection systems are more complex than simple mixer systems, they would naturally cost more. Of course, injection systems yield better results because of its precision in controlling the fuel flow.

Take note that when you’re comparing LPG conversion quotes, contrast quotes for similar systems to get a better grasp of the costs involved. There will also be some differences when it comes to factors like tank size and type, which could affect the final cost.


There are also several disadvantages to converting your vehicle to LPG.

  • Up-front conversion cost
    As mentioned earlier, you have to spend about AUD3,000 to AUD4,500 for an LPG conversion.
  • Servicing costs
    Your LPG fuel system would need servicing for every 12,000 miles or at least once a year. Then again, servicing LPG systems would cost less than those of diesel engines, and you'll spend on servicing costs regardless of fuel system anyway.
  • Insurance costs
    Some insurance companies may charge you an excess for an LPG conversion.
  • Availability of LPG stations
    While the number is increasing, not all petrol stations sell LPG.
  • Effect on warranty
    Factory-approved or factory-installed systems would naturally be covered by your car's warranty but conversions might not be.
  • Effect on vehicle space
    Installation of the LPG tank in the car trunk could take up significant space. If you're using a four-wheel drive vehicle, the LPG tank would be installed under the floor, reducing ground clearance.

Dual-fuel vs. LPG only

Conversion could entail two possibilities: either your car uses two fuels (i.e. petrol and LPG) or switches to LPG-only, essentially getting rid of petrol. There’s no difference in costs when converting to dual-fuel or LPG only, so you can choose dual-fuel systems to give you the flexibility to use either petrol or LPG.

However, an LPG-only system could offer you more fuel space dedicated to LPG instead of carrying two different fuels.

There are vehicle manufacturers that offer dual-fuel conversion kits and dual-fuel vehicles. Interestingly, the LPG-only vehicle models seem fewer as they run differently from regular petrol engines. Such engines have a higher compression ratio and an engine management system optimised for LPG operation.