Approx a year ago I financed a new car, and got it refinanced 6 months later. On at least my Experian CR, the original loan still shows as open with a significant balance, although it is reporting as current, never late. When I pull up the page on mycreditinform.com, it appears to be factoring into my utilization as well.
I had thought about disputing it, but I didn't know if I'm seeing a benefit from having the two auto loans in good standing, or if it's a negative from having a balance roughly double of what it should be. The overall utilization will stay roughly the same (the original loan is showing as 93%, the refi'ed loan at 95%, with the average reporting at 94%) if I get the original loan removed, but over time it will keep the utilization artificially high, which I think will hurt me in the future. I do also have two credit cards in good standing, never late, so getting it removed wouldn't wipe out my credit history.
I don't plan on getting another car loan ever again after this (working towards getting completely out of debt, and never again going back into considerable debt...basically just enough to keep a credit report active for purposes of other companies like insurance, utilities, cell phones, etc that base rates/deposits on credit), so I'm not worried about it from a future loan stand point, but I don't want a balance being carried to bring my score down for the other reasons.
I wouldn't worry about it ~ the balance will have no real impact on your FICO® score since it is an installment loan. The loan is in good standing so I wouldn't touch it.
+1 installment loans carry very little weight in Fico scoring