Per Google on that:
No, a Dana 30 and an 8.25 axle are not the same; they are different axles with different strengths, sizes, and applications, though both were used in Jeep XJs and could have similar early axle shaft spline counts. The Dana 30 is typically a front, reverse-rotation (high-pinion) steering axle, while the Chrysler 8.25 is a rear, non-steering axle with a larger ring gear, larger axle tubes, and a hexagonal-shaped housing.