Hi
1. First I assume you have owned for at least 6 months and have clear title and is purchased before you became a PR.
2. First you have to export from the US, for this you will require the title. See: http://www.cbp.gov/xp/cgov/trade/basic_trade/export_docs/motor_vehicle.xml
3. Note the US export offices aren't necessarily right at the border.
4. Then you have to import it into Canada if it is admissible. See: www.riv.ca