Tires haven't been rotated in a while -- well before the sound started,
but I had a slow leak in the driver-side front tire that got pretty bad
in the last month (down to 19 pounds pressure, maybe less, before I
could find a garage that was open and had a working airpump -- yes, I
now check them at elast once a week) The noise started after that
That tire has now been replaced to match the pair on the back rims.
Currently, I have 3 BF Goodrich tires, plus a Hercules. Yes, the
Hercules is gone at my next service call.
Still have the sound, but definitely get a noticeable vibration at the
100KPH mark. Not severe but there. Over that, still noise but no
vibration (what an excuse for speeding, not like this one ...
Tranny/driveshaft are untouched.
The otehr items are down for being part of the next service call --
three weeks time when I have a day off.
However, if anythign gets worse, its into the shop that day.