I have had that problem be intermittent and traced it
to a tire.  The problem did seem consistent at a
certain speed, ~43MPH.  Above or below, no problem.
Move the suspect wheel/tire and see if the problem
moves.

Stephen

--- Rick Koller <rkoller@HELIX.NIH.GOV> wrote:

> Greetings All,
>         I need help diagnosing a scary situation
> that has been intermittent
> so far. Here's the scenario:
> I'm driving my syncro westie straight down the
> interstate cruising at
> 65 mph, suddenly the steering wheel begins to shimmy
> dramatically,
> violent enough that I'm looking for the shoulder
> fast. I slow down
> and stop. Get out and look over the suspension
> parts, pulling and
> tugging on tierods, front and rear axles. I jack up
> the van and check
> for excessive play in the wheel bearings and any
> dangerous rumbling
> sounds from rotating wheels. I find nothing. I get
> back in the van
> and continue on and the van drives completely
> normally. No shimmy or
> shakes or rumbles. I'm wary now so prepare myself
> for another
> episode. Nothing happens for 3 weeks during this
> time I drive the
> camper daily at different speeds. Nothing happens
> until yesterday and
> the same scenario occurs, driving again at cruise
> speed of 65 and the
> dreadful shimmy starts out of nowhere. I pull over
> and do the checks
> again, still nothing obvious. I go on and the van
> drives ok below
> 40mph, as I get up speed the shaking starts again,
> this time it has
> some rumble or rubbing sound, can't tell what. The
> sound and shake
> goes away when I stop. I decide to try again and I
> get off the
> interstate to travel on local roads and keep my
> speed down. No
> problems at speeds below 40 mph, I don't push it and
> get home where I
> again jack up the camper and pull and rotate
> suspension drive axle
> parts. Still nothing obvious. Upper ball joints only
> a couple years
> old, new front axle on one side. Anyone have insight
> on this one? I
> scanned the archives but only came up with the usual
> bad tire
> scenario. Seems unlikely its a tire because of the
> intermittent
> nature, but who knows. Anyone?
> Thanks,
> Rick Koller
>

____________________________________________________________________________________
Sponsored Link

Get an Online or Campus degree
Associate's, Bachelor's, or Master's - in less than one year.
http://www.findtherightschool.com