This is possible but the person who owns the vehicle must also guarantee the loan. This sort of loan fits into the guarantor loans catergory.
Can I use GST as a deposit?
If the vehicle you are purchasing requires a deposit that you are struggling with perhaps the GST could be put into the purchase price when it is received after settlement.
How much of a vehicle's value will you lend to?
Depending on the the strength of your application and the type of vehicle a lender may fund up to 100% of the vehicle’s value or purchase price. They may require additional security or a guarantor to do this, depending on the vehicle or your credit score.