Bluewolf, mine was not there at Day 1.
As others have suggested, there may be other things (tires, even) that cause similar problems, but what I experience seems to be pretty much what Dick13 has described, and what I think is likely to be the same problem that (some?) GX470s have.
For me, the onset was at about 400 miles, centered around 1700 rpm, and noticable in 2,3,4,5th gear but not in Park. It has gotten a little worse with time and mileage. It now also happens (slightly) around 1250-1300 rpm. After about 6500 miles, the vibration and roughness got a little worse in the 55-65 mph range, and now happens also in 4th gear in that speed range.
As others have suggested, there may be other things (tires, even) that cause similar problems, but what I experience seems to be pretty much what Dick13 has described, and what I think is likely to be the same problem that (some?) GX470s have.
For me, the onset was at about 400 miles, centered around 1700 rpm, and noticable in 2,3,4,5th gear but not in Park. It has gotten a little worse with time and mileage. It now also happens (slightly) around 1250-1300 rpm. After about 6500 miles, the vibration and roughness got a little worse in the 55-65 mph range, and now happens also in 4th gear in that speed range.