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I've got a '89 YJ that I bought with a lift kit already installed. I beleive it's 2 1/2". Problem is when I have it in 4x4 and I'm cruising over 45 mph it vibrates really bad. The transfer case was not lowered, would that be the problem?? Also what is the best way to find out how much it was lifted?? I need to order new shocks.
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Check your drivrline angles, you may need a Slip yoke eliminator. That or you have some component failure in the front end.

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1990 4 Runner...tall, tippy, and purple.
1987 XJ ...shorter, stable, and Green
"going around is NOT an option!"
 

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I just finished my lift and had vibrations like crazy before i droped my transfer case. (1 inch)

good luck


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92 yj 2 inch body lift,lift shackles, 2.5 rancho lift springs running on 33's
 

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Superfly
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Originally posted by Brent:
I just finished my lift and had vibrations like crazy before i droped my transfer case. (1 inch)
If it only happens in 4wd then dropping the transfer case will probably make it worse since it is most likely a front drive shaft issue.

When you're travelling over 45mph, is this on a trail or pavement??

In any case, you should check the u-joints on the front drive shaft and the drive shaft splines for any damage or excessive wear.

...lars



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oh yeah i should mention that mine was vibrating in 2 wd

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92 yj 2 inch body lift,lift shackles, 2.5 rancho lift springs running on 33's
 

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i had bad vibes after recently raising my jeep 2" so to fix it i droped the t-case and inch but you could also put in shims or do a Slip yoke eliminator conversion
 

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I get some pretty bad vibes around at 75-80kph. I still don't know what it is though. I've tried different rpm's but at the same speed but it seems to not make any difference.

Sometimes when I go through a heavily travelled intersection and drive across the ruts in the road, It feels like the hole Jeep is going to shake to pieces,untill I slow right down then it is fine.

I have this extension bracket for my rear trac bar that raises it off the axle end about 3-4" I was told I needed this to compensate for the 4" lift...is this true. I might try taking it out and attatching the trac bar to it's original mount to see if that makes a difference.
I'm thinkin' that the vibration is coming from too much flex or instability in the extension bracket. Any suggestions?


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1997 TJ 4"lift. It's not what you drive, it's HOW you drive it.

[This message has been edited by 4Lo (edited February 21, 2002).]
 

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Superfly
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Originally posted by 4Lo:

I have this extension bracket for my rear trac bar that raises it off the axle end about 3-4" I was told I needed this to compensate for the 4" lift...is this true. I might try taking it out and attatching the trac bar to it's original mount to see if that makes a difference.
I'm thinkin' that the vibration is coming from too much flex or instability in the extension bracket. Any suggestions?
I doubt that the track bar would be the source of your vibration. The reason you need a longer track bar with that much lift is because there is now more vertical distance between the top and bottom track bar mounts. Because the track bar is a fixed length, the only way you could possibly bolt it back in without the extension is to pull the axle over to one side. By using an extension, the track bar's angle is lessned so it operates in an arc that is closer to the factory design which means there is less lateral movement through the range of suspension travel.

...lars

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Superfly
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Originally posted by DIGGER:
I do get vibration in 2wd, but only over 55mph. It's not nearly as bad as in 4x4 though.
I think you'd better go to Home Depot, by an angle finder (about $25) and measure the transfer case rear output, driveshaft and rear diff pinion angles. The first thing we need to do is deal with the vibration you get at high speed in 2wd.

Take those measurements and tell us what they are. If we can eliminate the possibilit of a bad driveline angle, we can go on to other things like u-joints.

Also, you never mentioned if this vibration at 45 mph occurred on or off the pavement.


...lars

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Senor Lars.. could you post that pic you had up on the forum a while back. The one that shoes how you used that angle finder.


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1997 TJ 4"lift. It's not what you drive, it's HOW you drive it.
 

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Because the track bar is a fixed length, the only way you could possibly bolt it back in without the extension is to pull the axle over to one side.
...lars

[/B][/QUOTE]

You are correct, I remember when the lift was first installed I did not have the bracket and the axle was off center...I believe it was to the passenger side about 1.5".


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1997 TJ 4"lift. It's not what you drive, it's HOW you drive it.
 

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Superfly
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Originally posted by DIGGER:
U-joints are new and it's on pavment
I would expect some kind of vibration when in 4wd and on pavement. Definitely avoid going into 4wd on pavement...it's not good for your drive train at all.


...lars



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Superfly
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Originally posted by DIGGER:
U-joints are new and it's on pavment
In that case, you should definitely measure the angles.

As for the diagram, I don't recall posting one. I think it was someone else who did.

...lars



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I am pretty sure it was you who posted a piture the pic was of an axle that was laying outside of an open garage and the angle finder was sitting on top. I could be wrong but like I said I am pretty sure it was you.If not then oh well I'm sure I can find the angle myself.


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1997 TJ 4"lift. It's not what you drive, it's HOW you drive it.
 
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