Looking at a 2001 Land Rover discovery 2 84 K miles very clean and well maintained. everything is very good, except the whine peaking at 40 ish mph and 70 ish mph. loud enough to make talking difficult rather high pitch. tried several surfaces from new and old black top to old cement sound was consistent, always there just peaked at the speeds??

 

Anything on your roof?
When is the last time you changed your gear oil? Could be transfercase and/or differential whine.

 

Thanks FishEH, that's what I was thinking, would that be a common problem at 85K? Rigs never been off road. been well maintained, recently replaced a drive shaft. Owner is 81.