Yes, a KBB can give you an idea for a good price to trade better privately, always below, but much better than in CarMax.
You can take it to get appraised, but I don't think you're going to get much for it. I'd sell it privately... I've tried twice to trade mine in and what they were offering me was way under Kelly Blue Book value!
Bring it in for a free appraisal. They take pretty much anything, but you might need additional money down depending on the value of the truck.
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