lol mate that is rubbish, auto f6/xr6t's have been run time and time again into the tens with stock engines, turbos and stock rear ends. even 9's. 4 spd auto was shit but the zf is a dam tuf box. manual utes have been known to break diff mounts with very rough driving, but still very rare. cv's and axle's do break but to someone with experience with last a very long time !!! your mate can't drive.