Rear axle

[Stuart Giles]

Is it the actual weld that's failed, or the material alongside the weld that's fractured? either way it doesn't look like the inner tube is doing anything other that aligning the axle tube. Having prepared the A7 tube's joint area with a proper "V" to ensure good penetration, I would also drill some holes around the periphery of the axle tube each side of the break and plug weld through onto the inner tube section. then weld all the way around the tube joint. Be prepared to straighten out some weld distortion once it cools down if you are using a proper amount of current for this job.