Sounds like you may have a bit of trouble getting the truck. The title for the truck is in his name, the loan was in his alone and no provisions were made concerning the truck in the divorce. Legally, it's his truck unless you can prove that he agreed to sign the truck to you once the loan was paid off. Otherwise, he used marital funds to purchase something in his name only.
Was the value of the truck considered during the divorce? Texas is a community property state, so any assets should be divided equally. Since he kept the truck, at the very least he owes you half of the value of the truck at the time of the divorce. I would check with your divorce attorney about that.
Otherwise, try to prove he agreed to give you the truck. Best of luck.
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