Sign's of UJ on the way out.
1 one of the four journals not taking grease. [ may last some time before it goes but go it will in the end]
2 new vibration while driving.
3 Looking at journals you may see rusty stains around the seizing cap.
4 clicking sounds, joint is not seized but is dry and that is taking its toll on the needle pin bearings in the cap
5 Classic sound of a canary bird singing underneath when driving.
6 Clonk and clatter when setting off, changing speed, changing gear.
At point 6 not much time left before the joint separates, the needle pins have gone, and journal is now wearing through the bearing caps.