Volvo says for 280DP, 290DP and DP:
0,0027" max runout gauged from the outer (tubular) to the inner shaft.
0,0012" slack when pressed the inner- towards the outer shaft.
You'd be surprised what your eyes can see.
Remove the prop and start it up.
Put it in gear and see if it has ANY wobble.
I was doing a LU service on one of my motors.
I removed the prop and greased the splines.
For some reason I spun the prop and noticed a big wobble.
Luckily it was just the prop and I had a spare.
Somehow the hub/ prop slipped or I hit something and it moved???