Are you the only one driving the Xterra? People have different driving styles from one another. Even yourself could drive differently on different days, and you may not even realize it.
Seems way too early, for your mileage to be so poor, to blame on any mechanical defect, but hey, I could be wrong.
Seems way too early, for your mileage to be so poor, to blame on any mechanical defect, but hey, I could be wrong.