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My auto loan that I kept, and reaffirmed, is not being reported to any credit bureau. They are not obligated to report so you cannot force them to do it. The reason that your attorney advised you to not reaffirm the loan was to protect you from liability for the loan should you have to give up the car for any reason. The car cannot be repo'd just as long as you are current with loan payments. That advice makes sense. Research reaffirmation if you want to better undertand the reasoning behind the attorney's advice.
Forget about the auto loan and get yourself a couple of credit cards and one small secured installment loan. That would be more than enough tradelines and mix to rebuild your credit.
I would first rebuild and then try to refinance the loan. If you try to now fresh out of BK you will pay more in interest. Read every single page of this thread and then read it 998667357 more times haha! Really though, it is a great plan and a perfect place to start.
Happy rebuilding