Legal Question in Consumer Law in Oklahoma

Re: How long does the car dealership have to secure my loan with a bank?

I don't know of any statute directly on point; this may be pure contract law you're dealing with, and I don't know of, nor did I find in searching, an Oklahoma case on point.

I also don't understand the out-of-state issue; you may want to ask for detailed, written explanation of that one. Assuming an out-of-state co-signer delays the approval, what would justify a bank's policy of raising a rate with a credit-worthy, willing co-signer, regardless of what state he lives in? Perhaps the bank wants in-state co-signers so it can more easily try to attach to their assets in event of default.

I agree it sounds like a spot delivery scenario, presuming there were blanks in the contract and you agreed to have the blanks filled in later; if not, you have a better argument. Your rights may hinge on the contract language you signed and representations made by the dealer; hopefully you have a copy of everything, and while it's fresh in your mind you should document all conversations you recall (and those going forward) with great particularity. Any claim you have may hinge on contract law; e.g., misrepresentation, unconscionability, fraud, breach of contract.