The appropriate repair depends on what has failed and the condition of the remaining components. An external leak may require a focused repair, while worn gears or bearings may call for internal work or replacement of an assembly.
A rebuild can involve replacing damaged components and carefully setting bearing preload, gear backlash, and contact pattern. In other cases, a replacement assembly may be a more practical option.
Certified Transmission at 2112 West Broadway in Council Bluffs can explain the findings, available parts, repair scope, and applicable warranty so you can compare the options for your vehicle.