What wpuld cause a roaring sound when power is applied to the rear axle?

A roaring sound when power is applied to the rear axle could be caused by several issues, such as worn or damaged wheel bearings, which can produce a loud noise as they fail under load. Additionally, problems with the differential, such as worn gears or insufficient lubrication, may also lead to a roaring sound. Another potential cause could be tire issues, such as uneven wear or incorrect inflation, which can create noise when torque is applied. It's important to diagnose the specific source of the sound to address the issue appropriately.