differential gear worn out

Camry 95 automatic 4 cyl (415000km), the differential gear is stripped . Do I need to change the whole tranny or just the diff. gear?. I understand that the transmission and diffrential gear seat in complete separated compartments therefore, there is no chance that the diffrential gear debris could interfere with the transmission gear. Is this correct?. Any comment would help... Many thanks

Camry 95 automatic 4 cyl (415000km), the differential gear is stripped . Do I need to change the whole tranny or just the diff. gear?. I understand that the transmission and diffrential gear seat in complete separated compartments therefore, there is no chance that the diffrential gear debris could interfere with the transmission gear. Is this correct?. Any comment would help... Many thanks
===
How do you know the differential gear is stripped?
Seems unlikely that those hardened, constant mesh gears would strip. Even if oil changes were neglected, would expect bearings to be affected first.
The differential in a '92 4 cyl. is separate though, so you're correct in saying any debris would be isolated.