What could be causing problem with front wheel hub having to be replaced

Hello, I would be concerned with the spindle that the hub rides on if you have had multiple replacements and the same problem occurs. Also, does your Mark LT have any modifications? Lowering kit? Aftermarket wheels or off-size tires? Any evidence of any damage / accidents? Have you had the wheel alignment checked, including SAI (Steering Axis Inclination) readings?

Inferior replacement parts is commonly the problem.