Ok, here's a fun one. My Jag S-type makes this odd rubbing noise, intermittently. That's the problem, nobody has been able to find out what it is because it's never happening when they test it. Sometimes when I'm driving at roughly 35 mph, there's this very rhythmic rubbing noise that sounds like it's coming from the right rear wheel (kind of a rump..rump..rump) type of sound. 1) I've got two sets of tires and wheels (summer and winter) and it does it regardless of which of them is on the car. 2) the car must be under power, if I take my foot off the accelerator the noise goes away. 3) It's most likely to do it going up hill, or when it crests a hill, never downhill. 4) It does it most frequently in the same places, i.e. there a gas station on the crest of a hill on my way home, it probably does it there more than anywhere else. Also a hill on the way to work that is a frequent location for it to happen. 5) Jag dealers have checked the car over and say the suspension looks fine. 6) There's no unusual tire or brake wear on the right rear, or anywhere else. The car is reliable, I take it on long trips all the time, just this one annoying noise that drives me nuts, and I'm sure it's a symptom of something that needs attention, it's just that nobody can determine what "it" is.