You should consider finding a local attorney who will give you a free consultation. However, I do not believe there is a way to get you off the loan. The finance company or bank has no incentive to release you from the obligation you agreed to take on. They want to be sure to get paid which is why they required a co-signer in the first place. There may be some remedy against the friend, but that's not in my area of expertise.
I agree with Mr. Ballard and unless you can prove the coercion you cannot expect to rescind your guaranty of the loan. The worst news is that even if you paid the entire loan you have no rights in the collateral. However you will have a case against the borrower and you will have a defense if they repossess the car and sue you for the balance remaining. You defense could be failure to join an indispensable party. Therefore, go see a lawyer and then maybe you can construct an offer and that will include information they need to get the car and eliminate you from further ongoing collection efforts once they have the car.
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I would have to agree with both of the other posters. Unless you can prove coercion, you might be better served to contact your ex-boyfriend, and insist he refinance and/or have a friend or family member agree to substitute in as a co-signer on the account. Really the creditor has no requirement to grant you a release, and unless you can make them more secure than they already are, they won't typically work with you on these types of matters.
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