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High Speed Vibration

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Old 07-23-2008, 11:50 AM   #1
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Default High Speed Vibration

I've experienced an up and down shimmy on the whole dash board assembly where I could feel it on the steering wheel and pedals. It feels as though it's coming from the front end or at least some place under where your feet rest; definitely not from the rear. It happens only in 6th gear at speeds above 70mph. It never shimmies in any other gear at any RPM; only 6th above 70mph. The shimmy itself is a little inconsistent, meaning that it comes and goes at various speeds above 70. However, the vibration unmistakably dissipates upon letting off the gas, and comes back a few seconds after I step on the gas again. I never step on the brake during this whole time, so I don't think it has anything to do with the rotors, especially since the shimmy responds to the throttle/torque.

For those of you who've dealt with this problem or are familiar with it, what are the common causes given the circumstances above?

Any input is greatly appreciated.
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Old 07-26-2008, 11:58 AM   #2
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have you checked your u-joints lately?
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Old 07-27-2008, 07:05 PM   #3
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Or the weights on the drive shaft and tranny mount? Although any of those things should cause the vibration at other times too.
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Old 07-28-2008, 10:21 AM   #4
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Quote:
Originally Posted by Drumer919 View Post
Or the weights on the drive shaft and tranny mount? Although any of those things should cause the vibration at other times too.

true... i just mentioned u joints because every one ive had has vibrated after a certain speed and went away when i let off the gas
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Old 07-28-2008, 04:12 PM   #5
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You could have a weight slung off if they put more than one on each wheel. It could be cords seperating in a tire, ball joint? Did you say it is in the front?
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Old 07-28-2008, 09:14 PM   #6
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i had that same problem with my old t/a after sliding across a median.(accident) turned out it was the weight on the driveshaft. it was missing. i would check for the weight and then replace the ujoints.
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Old 07-29-2008, 08:07 AM   #7
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all of the above things mentioned can cause a vibration thats for sure. Sounds like its time to get the jacks out and get to shaking
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