Is there any cost of getting the loan? Fee for paying it off early? And credits/rebates for using dealer financing? You can always get the loan and pay it off the next month if you have the cash on hand. It’s much harder to get equity out of your car.

But you’re paying 7% on money you likely have sitting in a savings account making much less… paying 7% with post-tax money is like turning down a guaranteed 9% return. The only time that makes sense is if you are avoiding a higher interest rate elsewhere (need an unsecured loan for a home improvement, would use a CC with a high rate to cover expenses if you lost your job, etc).