[jeepcaptain]

I know someone on here will have the answer, because they always do. Here it goes. I have an '03 Rubicon with a 3" Rubicon Express lift, 1" body lift and a cv driveshaft, 5 speed by the way. I've developed a vibration between 25 and 40 mph(2WD) that occurs only when I am accelerating. Push in the clutch and or let off the throttle and it goes away. I'm new to this but it seems to me that it could be an allignment issue maybe due to worn out shocks or ???. I have 33's and do a lot of highway driving up to 80 mph with no real vibration above or below 25-40mph. Any help would be greatly appreciated. Thanks, Zane.

 

[f9k9]

If, it is more like a shudder then, I would look at your RE CA bushings.

 

[jeepcaptain]

Thanks f9k9. They do have a few cracks. As far as a shudder versus a vibration, i'm probably not smart enough to tell the difference. I can really feel it in the steering wheel and sitting in the pass seat.

 

[gregert12]

Zane,

If your bushings are fine, I would check the tightness of the trackbar and your steering components.

 

[jeepcaptain]

Greg, my steering components seem fine. The rear track bar isn't what I would call "loose" but it does rotate on the ball joint pretty easy at a level stance.

 

[f9k9]

Thanks f9k9. They do have a few cracks. As far as a shudder versus a vibration, i'm probably not smart enough to tell the difference. I can really feel it in the steering wheel and sitting in the pass seat.

OK, the shudder is not in the equation because, you would feel it immediately from 0-whatever speed. Don't knock your intelligence and call yourself "not smart enough". I am a newbie after 4 yrs of chasing stuff. We all keep evolving and learning. I jumped on the bushings because you said that it happened in "2wd".

Back to basics. I understand you to say that it was fine before and recently developed this problem? It starts at a certain speed and as you accelerate out of the problem speed area, it stops.

Have you already checked all fasteners and made sure that they were at the proper specs? I often blow this off because I checked it 2 weeks ago and I have assumed everything is still okay.

 

[Eric]

vibration under acceleration is usually caused by a rear driveshaft issue, either bad angle, bad u joint, out of balance etc.

 

[gregert12]

I would rotate the tires and see if that fixes the vibration, it could be that a tire lost its balance.

 

[Squatchy07]

vibration under acceleration is usually caused by a rear driveshaft issue, either bad angle, bad u joint, out of balance etc.

This, possibly caused by bad CA bushings.

When you accelerate, your rear axle may be rotating due to worn upper rear CA bushings. I had the same issue before I started running Johnny Joints. Sometimes would make a popping or rattling sound when changing between reverse and first gear or vice versa.

Joey

 

[jeepcaptain]

Thanks again everyone for all of the good directions to go. It just started a few weeks ago and appears to be getting worse. As soon as you let off of the throttle it goes away so i'm leaning towards a linkage problem and/or the pumpkin not in the correct angle with the transmission. I wonder if worn out shocks would cause enough change in angle to cause this. Thanks again. Will let ya'll know what I find in the coming days. Roll Tide!!!!!

 

[blk03rubi]

i had the same thing happen..... have you checked your u-joints?

 

[jeepcaptain]

I had to do some serious searching for it but found a slightly worn u joint at the back end. It had a very, very small amount of play but it sure was causing a lot of vibration. Thanks again for everyone's help!

 

[blk03rubi]

I had to do some serious searching for it but found a slightly worn u joint at the back end. It had a very, very small amount of play but it sure was causing a lot of vibration. Thanks again for everyone's help!

Sweet!