[Pooke]

I have a 95 2.0 v6 Escudo Auto and I have a drive train whine.

It is really only noticeable above 50kmh and is worst around 70kmh and pretty constant. It is noisier under load, if I put it in neutral and coast, or even just coast in drive it is quite alot quieter but still there. No difference between 4wd or 2wd.

Would this be symptomatic of a rear diff bearing? possibly pinion?

No play in driveshaft nor any leaks. Breather had come off rear diff and a small amount of water got in, though not alot.

[Gwagensteve]

You've answered your own question. Time for a rear diff rebuild