Some car loans require a lien in favor of the bank or use other guarantees and arrangements until the loan is fully repaid.
Steps
If a lien is in place, you cannot transfer ownership normally until it is lifted after settlement or with the bank's approval.
Before signing the contract, ask who holds the documents, when and how the lien will be lifted, and whether there are any fees or processing times after the final payment.
The figures, fees and limits in this answer vary by bank and change over time — confirm them with your bank or the official source before acting.