My 2000 xjr has developed a sound similar to the many trucks around here that have mud tires. The sound speeds up as speed increases and seems to be coming from the rear but without having someone else drive by me, its hard to tell. Anyone heard or experienced something like this? The tires look good and ride normally.
Sounds like might be internal belts on tires have separated - how old are they - if not that, suggest checking differential bearings, u-joints, and wheel bearings.
Is it load related or just speed? I‘d swap front and rear tyres (if same size) and go from there if it depends on speed only.
Robert is it a drone? As others have said, if the tires are over 4 years , its time to go…
Michelins willlast the longest and kill the drone, bf goodrich along with others will kill the shifted belts.
IMHO though michelins are the best.
If your not rallying around