Just Another TJ Vibration Issue

SherryXTJ

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Jun 18, 2019
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Location
Missouri
My 2004 Jeep Wrangler just randomly started an acceleration vibration a couple of months ago. I was just driving down the highway, no bumps or jerks. I drove with it this way for about a week and decided it was not going to work itself out. My mechanic changed out the pinion yoke and the rear u-joint. I had the tires rotated as well. No change at all. After another week I asked him to try again. He opened up the transfer case, nothing wrong, and changed out another u-joint. He checked everything. He or the owner can't find anything, even called their transmission guy and he said it wasn't in the tranny. What's going on? It vibrates no matter what gear, no matter the rpms, and usually when I am getting up to 20mph, as long as I am accelerating. Do any of you have any ideas? Thanks so much!!
 
Could be a bad u-joint. Have you greased them all and gone over them?

In addition, it could still be the wheels / tires.
 
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My 2004 Jeep Wrangler just randomly started an acceleration vibration a couple of months ago. I was just driving down the highway, no bumps or jerks. I drove with it this way for about a week and decided it was not going to work itself out. My mechanic changed out the pinion yoke and the rear u-joint. I had the tires rotated as well. No change at all. After another week I asked him to try again. He opened up the transfer case, nothing wrong, and changed out another u-joint. He checked everything. He or the owner can't find anything, even called their transmission guy and he said it wasn't in the tranny. What's going on? It vibrates no matter what gear, no matter the rpms, and usually when I am getting up to 20mph, as long as I am accelerating. Do any of you have any ideas? Thanks so much!!
Was there a specific reason the mechanic gave you for replacing the pinion yoke?
 
You could narrow out the the drive shafts by removing one and driving - then switching which is out. Another idea is to check your front hubs/unit bearings.
 
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Thank you all — I will be taking time to look into all of these suggestions. Hopefully will come up with a fix!
Take care!
 
I'd be looking at that pinion yoke. If the mechanic changed it out then it worked it's way loose over about a week, take it back to him and have him check the torque specs, make sure it's right
 
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I'd be looking at that pinion yoke. If the mechanic changed it out then it worked it's way loose over about a week, take it back to him and have him check the torque specs, make sure it's right
Yep , you do not want a loose pinion nut.

If it's loose , sit him down and make him listen to "Jeep Gang " by Katie Noel 30 minutes as just punishment by the TJ Forum .

He won't let it happen again .
 
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X2 on removing one driveline at a time could need balanced
The first thing you do with a Driveline vibration is pull the front shaft.

This does not dictate that it is the front shaft causing the problem but it is at least isolates the front shaft.

Sometimes you can have a problem in the front Driveline that is communicated to you by way of the shaft... And you can also have a harmonic vibration that only appears when both shafts are turning... In either case removing the shaft makes the problem go away.

Most of the time the front drive shaft is generally ignored and the joints end up dry and you have a problem with a U joint or the double cardan.

Sometimes doing this takes the transfer case chain out of play and ultimately you find out the vibration was the transfer case chain.

You can also have a drive shaft that has somehow became damaged and is out of balance.



In my opinion it's most likely going to be something in the front drive shaft if removing the shaft makes the problem go away but that's not always the case... In other words the components that are most likely to be worn are the U-joints or the double cardan.
 
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