Auto Refinance Calculator
A lower payment isn't automatically a better loan. This shows the monthly savings and the lifetime cost — including the trap where stretching the term makes a cheaper rate cost you more.
The whole picture
New monthly payment
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Current payment
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Monthly savings
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Lifetime savings
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Fee break-even
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The term-extension trap
Refinance $22,000 from 9.5% to 6.5% and keep your remaining 48 months: you save on both lines — lower payment, less total interest. But reset to a fresh 72-month term and the payment drops much further while the lifetime cost quietly rises: you're paying interest for two extra years, which can eat the entire rate improvement and more. Most refi calculators show you only the payment line. Both lines are the deal.
When an auto refi genuinely wins
Rates dropped, your credit improved since the original loan, or you overpaid at the dealership (dealer-arranged financing routinely carries a 1–2 point markup the lender kicks back). The clean move: refinance at the lower rate and a term equal to or shorter than what you have left. The gray move: extend the term because you need the cash-flow relief — legitimate, but do it knowing the total price.
What to check before signing
Auto refis are cheap to close (usually a title-transfer fee plus at most a small lender fee — no appraisal, no title insurance), so break-even comes fast when there are real savings. Check that your current loan has no prepayment penalty, that the new lender doesn't pad the payoff quote, and that GAP coverage carries over if you have it — it usually doesn't transfer automatically.
One more thing for 2025–2028 loans on new US-assembled vehicles: refinancing generally keeps the car-loan interest deduction on the refinanced balance, per IRS guidance — so the deduction is not a reason to stay in a worse loan.