Don't want to get too technical here, but before MetroI and MetroII standardized the way creditors report to the bureaus, creditors did not have give every little detail about the account. Most of the time, creditors did not have to report the account type because it was assumed by their kind of business. For example, a car finance co didn't actually have to report that it was a car loan, because the bureaus knew that the only kind of loans that company gave out were car loans, and so it was kind of up to the bureaus to code the account type.
After FCRA was implemented and MetroI standardized the way creditors report, that's when the bureaus started cracking down and making the creditors report the account type for each tradeline they reported (instead of just assuming by the KOB).
Most likely, your car note fell into those times when the creditor didn't have to specify what kind of loan it was. And now 10 years later, because the creditor never set the account-type flag back then, the bureaus don't know what kind of a loan it is now.
Chances are, if you dispute it, it will just get deleted. That company may not even be in business anymore - in which case it would definitely be removed. I don't think it's hurting your credit, because it is showing paid satisfactorily. Besides, if it was bad, then it would have naturally come off 3 years ago. It's up to you whether you want it on or off, like I said I don't think it is hurting your credit.