The only way an axle will snap is if you get traction, in my FJ20T ute it had a stock and locked diff which had no problems till i ran at eastern creek where its a lot sticker than the street and it snap on a 6000rpm launch.
My mates own a CA18DET which makes bout 220hp at the wheels and has been running the same locked ute diff for 3 years now just because the car never has any traction to snap anything.

your diff want go its welded the only thing that will happens to that is you my snap you welds depending on how you locked my has plates and all in there .
Cheers Luke