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Discussion Starter #1
have a Tom Woods shaft. and R.E. 3.5'' long arm installed.
have not used the jeep much untill fri was sitting in my garage most of the time ..(using a work veh. due to standby duty)
last fri am i took my jeep out and played in some local hills..

well now ive pegged the fun factor and started having some vibes..
started out with a shudder at takeoff speed..and got more pronounced.

we looked at the dirive shaft angle and thought hmmmm might be a tad to high so we lowerd it.. now the shudder is gone. the vibe returns at
approx 42 MPH and stays till about 50, then disapears...

now my question is whats causing the shaking?
is it the front driveshaft? due to the angle has changed..
or raise the rear back up a tiny teeny bit....
???

open for suggestions..
mac
 

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Discussion Starter #4
Ned said:
Is it a CV or double cardan style shaft?


TW shaft this is the first one they sent me IT WAS TOO LONG ...
Notice how ther is no room for compression..
new shaft has approx 1'' space for compression.

i need suggestions.. as i dont wana tear up sumthing with the vibes.

mac
 

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Fron the look of you pic your pinion is about 4 deg to high. You definatley need to get a new shaft. Even though you don't have any compression that should not cause a sudder when you start off. I would also check you skid and make sure that everything is tight at that end. I have heard of many people having vibe issues due to the stock skid not being strong enough. I know that you are running an RE skid that is why I would suggest checking that everything is torqued there.


First off change that pinion angle......The pinion should be 1 deg lower than the shaft angle.

Cheers.
 

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4x4mac said:
Ned said:
Is it a CV or double cardan style shaft?


TW shaft this is the first one they sent me IT WAS TOO LONG ...
Notice how ther is no room for compression..
new shaft has approx 1'' space for compression.

i need suggestions.. as i dont wana tear up sumthing with the vibes.

mac
in that picture there your pinion is at leat 5-8 degree's too high - Rule of thumb if you can see the difference its more then 5 degree's - Jesse
 

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I believe the picture is of his first drive shaft!!! Not positive tho!! :)
 

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Discussion Starter #8
oh my i forgot how pisssssssed i was when i picked up
my jeep from the install shop....
your right the pinion angle was WRONG....and the DS
was WRONG...
tis all good now.
:D
 

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I have the same issue with vibes. I have the RE 4.5" SF lift and adjustable rear trackbar. I've adjusted the pinion about 20times, replaced the TW adapter flange, had the DS re-balanced, and still no luck. I think the problem is that the whole unit needs to be balanced together (stock flange, dampner, TW adapter flange and DS). From what I've read most people with Rubi's and the TW Rubi Package have this issue. I hate to say it but your just gonna have to live with it.

Does anyone know if a standard Driveshaft Shop has the equip. to balance everything together?
 

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BlackSahara said:
I have the same issue with vibes. I have the RE 4.5" SF lift and adjustable rear trackbar. I've adjusted the pinion about 20times, replaced the TW adapter flange, had the DS re-balanced, and still no luck. I think the problem is that the whole unit needs to be balanced together (stock flange, dampner, TW adapter flange and DS). From what I've read most people with Rubi's and the TW Rubi Package have this issue. I hate to say it but your just gonna have to live with it.

Does anyone know if a standard Driveshaft Shop has the equip. to balance everything together?
Most shops do not have the machine to do this- We have spent about 10 hours making a fixture to fit our high speed balancer 4000rps. aprox. 95mph vehicle speed- Jesse
 

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Vibes

Before assuming it is the rear DS, espcially after all the adjustment, try changing the front DS angle slightly - shoot to keep your caster angle at 6 degrees. I went through what you are describing - with a small pinion angle change (up) in the front, all was good!. You could not imagine the shaking and noise the offset caused - I would swear my front DS was going to fly out at highway speed.
 
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