vibration/shudder at 70 - possible alternatives (other than wheel balance?)

[txrocco@sbcglobal.net (Patrick Bureau)]

Hell if I know...

I have the same problem, and I have changed everything
ball joint, complete tie rods/& ends, rebalance
(underload tire balance) have hub centric shims, done
2 alignmnet to make sure, (second one came out
perfect)
but camber was in need to be fixed (need camber strut
kit for that) Half shafts are new (rebuilt).

all I can think at this point is that it is the camber
(left is negative 2, right is positive 3)

whatcha think ?

--- Allyn <amalventano@sc.rr.com> wrote:
> ok, the rieger has had the same shudder at 70ish for
> the longest time.
> 
> things changed:
> a-arms, bushings (all), bearings (all), half shafts
> (replaced with a
> questionable set), engine/tranny, engine mounts, and
> a totally different set
> of wheels. not to mention rotors and hubs (i think
> this covers just about
> every moving part).
> 
> ...and yet i still get the shudder...
> 
> exact symptoms:
> 
> - 0 vibration felt in wheel, even with the shudder
> at its worst.
> - alignment is close enough such that it couldnt
> cause a problem like this
> - shudder is not constant, the vibration is
> consistent with wheel rotation
> at 70 mph, but it comes/goes at a 1 second cycle
> (kinda like its amplitude
> modulated).
> - shudder seems proportional to throttle
> application. the other day i did
> several runs on the highway, coasting from 90-60 in
> neutral, and the shudder
> seemed to go away. shudder returns when holding
> speed at 70, and gets worse
> under acceleration.
> - feels like an out of balance wheel, but i've also
> felt the same feeling
> when i had a bad inner cv (however the bad inner cv
> had a constant
> vibration).
> - also seems like bad inner cv in that its almost a
> side-to-side vibration,
> felt in the floor under the center console.
> 
> possibilities:
> 1. other set of half shafts (rebuilds from
> potterman) had the exact same
> problem with the inner cv.
> 2. frame/engine is misaligned such that one of the
> half shafts is at its
> compressed limit when installed / car on ground.
> possibly forcing tranny
> over as it rotates, causing the vibration.
> 3. both sets of wheels/tires have had the exact same
> imbalance, after being
> balanced several times between both sets
> (doubtfull).
> 
> suggestions???
> 
> (thx in advance for info)
> Al
> 
> 
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