You always need an emergency fund. What happens if you pay off all the loans? A, you still need a car -- so now you're replacing one type of debt with another. And B, if something hits, how do you pay for it? You put it on a credit card -- in which case you've just swapped a 6% loan for a 15-20% loan.
I applaud you for wanting to get those loans paid off -- that is so much better than what many people do with any extra cash! But you need to look at the bigger picture. What are the rates on auto loans? If they're cheaper than the student loans for a @$4K used car, then by all means, swap higher-rate debt for lower-rate debt. But whatever you do, save yourself enough cash to cover your anticipated upcoming "extras" and things like a blown tire or an ER visit, so you don't end up diving back into even worse debt. So pay off one of the loans, maybe two if you can get a better rate on the car loan. And then use your hatred of the remaining debt as motivation to really tighten the belt and cut expenses and work your ass off on your side gig to get the rest paid off ASAP.
