WIll this cure those rear end vibration issues ? (1 Viewer)

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Beast,

No. If your vibrations are from the rear shaft almost falling out, then yes. But if that's the case they'd have wiped out in just a few weeks of driving.

Vibrations in lifted vehicles are almost invariably related to the increased angle of the drive shaft joints. The more the angle, the greater are the axial forces due to the design of the joints. You can cure it by rotating the axles so that the angle is reduced again, or by installing double cardan joints that are able to handle greater working angles.

Doug
 

Vlad

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I believe that product exists due to the aussie crews having MUCH larger lift heights.
 
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I know this is an old post, but I'd like some clarification on this issue since I have a little vibration w/ 6" lift.

Correct me if I'm wrong, but I thought that to minimize having any vibration in your drive shaft you want both ends of joints to have the same angle so that they cancel each other out. Unless of course you have a double cardan joint shaft.

Carl
 
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robbie

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That product will not doing anything except help with the slip joint from falling out. If you have a 6 inch lift with nothing but stock bumpers (ie no extra weight other than stock) your lift will be higher. So my question is what year, how's lift, what other things do you have on your truck, what weight do you carry in the back?
Other questoins? do you feel it in the seat of your pants or in the steering? Is it more of a vibrations or a sound you hear? later robbie
 
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Robbie,
It's actually a humming noise that I have. My '96 has Slee's complete 6" Kit, 315/75R16 on 16x10 rock crawlers, Kaymar rear bumer w/tire carrier and full spare, gas can carrier, custom sliders off George's design, and stock frnt bumper. The only time I really hear it is when some of the load is off the drive shaft. For example, when I'm driving on the freeway and I let off the gas, but then apply just a little pressure you can hear the humming noise. Even if I'm towing my 3600lb boat I don't hear the hum, unless I do the following procedure above. Oh, the noise is coming from the center console area.

My concern is if there's a vibration issue with the shaft, will it wear out the joints faster and/or will there be harm in the long run on the 3rd member and t-case?

Carl
 
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robbie

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Did you install the lift? fi so did you max out the adjsuter on the upper control arms in the rear? Did you have the u-joints checked? Some times older u-joints that have worn in one positions and then drastically change will create a hum like you are describing. If the u-joints are OK then I think you would be a canidate for the CV style drive shaft. vibration can create some extra wear on the input to diff bearing and the out put bearing in the t-case. hope this helps you, later robbie
 
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Here....mostly.
Carl,

Welcome to the board and the club...check out this thread.

https://forum.ih8mud.com/showthread.php?t=17536

This is how I understand it from that thread, Slee, and other drive line shops I'v chatted with.

When you lifted your truck, the rear pinion is forced down. The more you lift it, the more the tilt in the rear pinion and the more the transfer case and pinion become out of plane with each other. Under normal acceleration, the torque on the pinion causes it to raise...thus decreasing the angle, and conversly when you decelerate the pinion is torqued in the opposite direction giving you more of an angle offset than you have sitting still. This is why you only get it decelerating from high speeds, and why applying a bit of gas causes it to suside. Slee sells adjustable upper controll arms to allow you to lengthen the stock arms and move the pinion back to its stock configuration. This very well may get rid of the vibration. If not, the same adjustable arms can be used to shorten the stock arms and point the pinion up the the t-case in which case you can use a CV joint in the rear driveline to eliminate the problem.

Hope this helps.
 
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First of all, thanks for the welcome and advice Safado & Robbie.

Yes I did install the kit along w/ help from a couple of buddies. I do have Slee's adjustable upper control arms and they are adj. to the shortest length which I believe is only about a 1/2" shorter than stock. I thought you are suppose to shorten the arm instead to minimize the vibration/noise? I checked the Uj's at the time and they are good, but will check them again tomorrow. Safado, I read that thread and this just confirms the conversation I had with Ben at Slee's about the rear drive shaft issue when lifting your rig. So looks like I'm gonna have to invest in a double cardan shaft soon since I don't want to reck havoc on the other components of the driveline. Otherwise, I could deal with the noise if that was the only issue.
 

MTNRAT

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I have the 6" lift and the installation of a double cardan rear driveshaft solved all vibration from the rear driveshaft.
Cheers,
Sean
 

alia176

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Safado said:
Carl,

When you lifted your truck, the rear pinion is forced down. The more you lift it, the more the tilt in the rear pinion and the more the transfer case and pinion become out of plane with each other.
Hope this helps.

Sorry, but I don't follow this logic... :D Is the pinion forced down or the is Tcase forced up? The pinion stays in the same angle in the rear, hence the bad angle :confused:
 

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