TTORA Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
186 Posts
Discussion Starter · #1 ·
I've got on 06 Access Cab lifted 3" and have the same slow speed/high torque vibration problem everybody else has with these two piece drive shafts. Matching the driveline angles just doesn't fix it, period. Shimming the carrier bearing is the only thing that helps.

I've heard that you shouldn't shim it more than 1/4". While that helps, it takes 0.300" to 0.500" to really eliminate the vibration. Obviously this screws up the angle of the forward U-Joint by the transfer case. But why else would anything more then 1/4" be a no-no? It doesn't cause excessive vibration at highway speeds and it stops vibration at slow speeds.
 

·
Registered
Joined
·
1,090 Posts
If I am interpreting your question as intended you are wondering about what affect the angles have on u-joints? U-joints will wear out faster with more increased angles. Im not sure about other stuff but it is just optimal for the u-joints to be straight on. I would think that as long as you are fine with possible reduction in u-joint lifespan that you could shim it more than a 1/4". Im sure others will have better advice.
 

·
Registered
Joined
·
2,364 Posts
Been there, done that. At .500 shim thickness, the front joint causes vibes and you get a harmonic at freeway speeds. Have you shimmed the axle yet? There is no simple solution, just one big science project.
 

·
Registered
Joined
·
186 Posts
Discussion Starter · #4 ·
Have you shimmed the axle yet?
Yeah, the angles are perfictly matched before shimming the carrier bearing. I'm going to shim it to .300". I just wanted to make sure there wasn't anything weird that made the forward u-joint overly sensitive.
 

·
Registered
Joined
·
449 Posts
I hate how finicky these fucking trucks are, my truck is real bad with the vibe issue. I may just get a one piece shaft. I stil don't see how a one piece shaft fixes it though because the tranny is straight out not angled and the angle would be off there then, unless that just doesn't matter.
 

·
Registered
Joined
·
186 Posts
Discussion Starter · #6 ·
I stil don't see how a one piece shaft fixes it though because the tranny is straight out not angled and the angle would be off there then, unless that just doesn't matter.
I think they use a CV style joint at the transfer case end or double cardigan (which I'm not sure of the theory behind).

If the pinion is parallel to the output of the transfer case, and none of the angles are too extreme, does it really matter how much the carrier is shimmed? Wouldn't the input vs. output velocitys remain constant throughout a single revolution? Seems like something a little bit of math could prove, anybody know this not to be the case?
 

·
Registered
Joined
·
449 Posts
Well I am waiting for my Dakars I hope the vibe is helped with them however I am sure it wont be since the lift the rear so much. I have heard that some leaf packs though are angle to compensate for lift. Whether that is true or not though I don't know. I hope I am able to get teh problem fixed though easily without having to get a one piece shaft.
 

·
Registered
Joined
·
2,364 Posts
Well I am waiting for my Dakars I hope the vibe is helped with them however I am sure it wont be since the lift the rear so much. I have heard that some leaf packs though are angle to compensate for lift. Whether that is true or not though I don't know. I hope I am able to get teh problem fixed though easily without having to get a one piece shaft.
I installed my Dakars and got a little bit of vibe back. I also modded my trans x-member, dropped it .500 to help the vibe issue. I wrote a big post on this. It's a real freekin science project. Now I have to play with it a bit more since the Dakar springs gave me more lift.
 
1 - 8 of 8 Posts
Top