Can I pay off my car loan early?

In most cases yes, and doing so saves interest on a typical simple-interest auto loan. Check your contract for a prepayment penalty, which some states restrict and many lenders don't charge. When making extra payments, ask the lender to apply them to principal. Get a payoff quote before paying the full balance, since it's calculated to a specific date, and confirm the lender releases the lien so you receive a clear title.