Estimate Your Monthly Car Loan Payment Auto loans are amortized installment loans, so once the terms of your loan are set, your payments should stay the same month after month. Assume you are taking a $20,000 car loan, for a term of 48 months, with an interest rate of 3%. Use this calculator to answer the following questions. 1.What is your monthly payment? 2. What will happen to your monthly payment and total cost of the loan if you increase your down payment? 3. What will happen to your monthly payment and total cost of the loan if you secure a lower APR? 4. What will happen to your monthly payment and total cost of the loan if you lengthen the term of your loan? 5. What will happen to your monthly payment and total cost of the loan if you pay more than the minimum monthly payment? 6. What are two reasons why someone might purposely choose a higher monthly payment?