1983.5 1.9 H2O Manual transmission.

I have what sounds like a wheel bearing noise from rear or van -it's noticeable above 40kph, rises and falls with the speed of the van,not engine rpm and really noticeable when van slows from 80 to 40kph.

Repacked CV axles- no change, but with someone riding in the back it appears that the noise is coming from the transmission.

Any ideas?
Thanks
Gerry