If the RV loan is secured by the RV, you can deduct the interest, even if you did not receive a 1098.
If the RV loan is unsecured or is secured by some other property, even including your main home, the interest is not a deductible.
If the RV was financed by the mortgage on your main home, it counts as equity debt and you can’t deduct that portion of the interest from your primary mortgage either.
