I had a similar problem recently. It happened after tire rotation and
balancing but had nothing to do
with either. It turned out that the tire place over-inflated the tires.
Manufacturer recommends
26 psi for normal driving. They inflated the tires to 34 psi when I noticed
extreme vibration and
then checked the tire pressure the following morning when the tires were
cold. After I lowered
the pressure down to 28 psi, most of the vibration was gone. Some damage to
the tires might have
already happened.

"TL" <tlehman@visi.com> wrote in message
news:5kithvkk1sndsri3m0hcmc0s6199r9htn5@4ax.com...
> I very much doubt that it is RPM related or you would see it at other
> speeds in other gears. The classic symptom of a tire out of balance is
> a vibration that sets up somewhere around 55-65 and is absent above
> and below that speed. Sounds like what you have. My guess is that a
> tire has been out of balance tire.
>
>
>
> On Sat, 19 Jul 2003 03:05:16 GMT, Steve Lee <dont@thinkso.com> wrote:
>
> >I just came back from a vacation and noticed on the highway that my
> >Pilot was vibrating, while not violently, but still noticeably, when I
> >eased into the 60MPH mark with the RPM between 1700-1800RPM. If I
> >were to approach the 60MPH mark with the RPM at a higher level, I
> >never got it and once I stepped on the gas a bit harder, thus bringing
> >up the RPM and getting past the 60MPH mark, the vibration disappeared.
> >
> >I did check the tire pressure, the transmission fluid level and all
> >were fine. However, I did notice that the oil level was slightly
> >higher than the high mark on the dipstick. It was higher by about a
> >diameter of the circles on the dipstick.
> >
> >Being back in the city just yesterday, I haven't been able to
> >duplicate the situation because it's hard to find enough room on the
> >road, even on freeways around here, to be able to gently get up to
> >60MPH while the RPM is at that relatively low range.
> >
> >It happened whether I was going uphill, downhill or on flat roads.
> >Also, it started happening towards the latter part of the trip, even
> >though I'm pretty sure that I had driven my car such that it would've
> >duplicated the same condition earlier in the trip.
> >
> >Can anyone guess as to what might have caused this? Being a holiday
> >trip, the rear cargo area was filled with the usual stuff, such as
> >iceboxes, suitcase, food containers and etc. But I'm positive the
> >total weight still would've been well under the cargo limit, even with
> >weight of the passengers included.
> >
> >I have to take the Pilot in on Monday to get it serviced and plan to
> >mention this problem and perhaps go for a drive with a technician,
> >hoping to be able to duplicate the problem. In the meantime, if you
> >guys can suggest a possible cause for this problem so I can mention it
> >to the technician, it'd be greatly appreciated.
> >
> >Thanks for your time and courtesy.
>