I have an income of roughly ~70k, a little over $50k after taxes. My only debts are housing expenses (rent and utilities) which total around $800 out of >$4000 a month net income. Recently, I was rejected for pre-approval on an auto loan for $20,000. However, they said they'd be willing to consider the loan if I brought a purchase order from the dealership.
What's the difference between pre-approval and getting the actual loan? Why would I be denied based on the information I provided?
Edit: My FICO score is 770+. I've checked it a couple times in the past couple months. Once it was 805 and another time it was 777.