More info.
(bighorn 1996, 4jg2 UBS69)
Brake pads done, engineer spotted lots of gunge rear left. (Axle seal probs)
Today Greg and the guys at Ruakaka motors pulled the thing apart. Bearing OK, seal damaged. Replaced seal checked things and put it together again. No ABS light on the way home.
I'm "Cautiously optimistic"
Thanks to all who advised and to Greg and the team.