I don't think the transfer of vehicle applies to you in your case since you are not tansferring to your family member related to blood (unless you get married right away of course..
For your case, I'd say you treat it the same way as selling a used vehicle to others (info at
http://www.mto.gov.on.ca/english/dandv/vehicle/used.htm). For your information, here's the extract from MTO:
"Tax Exemption
Payment of retail sales tax is not required when a vehicle is a gift and is being transferred between close family members, which only includes a spouse, parent, step-parent, grand-parent, son, daughter, grandson, granddaughter, son-in-law, daughter-in-law, father-in-law or mother-in-law. Only one tax-free transfer per vehicle is allowed every 12 months.
A statement sworn before a Commissioner of Oaths will be required for certain transfers, such as gifts between family members and transfers for insurance purposes. Diplomats and Status Indians who qualify will be able to complete a transfer without paying tax by simply showing their identity card."