Hey, any one have an issue with their JK feeling like it is on a washboard dirt road at certian rpm. i have 3" lift and at 1200 to 1400 rpm, around 40 mph, thier is a vibration like you are going down a washboarded dirt road. i have rotated the tires and no change. the feeling is not in the steering wheel, it is in the body. is this a sign the u joints are going out due to the lift? scott

 

do you have aftermarket drive shafts installed? and, if so, did you make sure to set your rear pinion angle so that it's in line with your drive shaft?

 

I haven't experienced it, but from your description it looks like you are experiencing the Death Wobble. Look it up, there is plenty of information about it.

 

trust me, if you have experienced death wobble, you wouldn't be saying this. what he's describing is a very heavy "vibration like you are going down a washboarded dirt road". he specifically says that "the feeling is not in the steering wheel, it is in the body". death wobble is something that make your whole jeep feel like its tearing itself apart and the only way you can make it stop is to bring your jeep to a stop. everything i am hearing is point to a rear drive shaft that is not set properly or, is severly out of balance.

 

No - the OP's description of the problem is NOTHING like death wobble. As WOL said, the fact that it is speed-dependent is indicating that it's a balancing issues - either driveshaft or potentially tire/wheel. Sending him looking for death wobble fixes will just confuse him.

 

the drive shaft is stock. just at the rpm there is a shake. when you increase the rpm the shake goes away.

 

a tire guy i know did not think it was a tire balancing issue, it is not in the steering wheel. just at the rpm range while crruising without applying more gas there is a shake. when you increase the rpm the shake goes away. driving on the highway there is now wobble. it is rpm dependent.

 

is there a write up for rear drive shaft installation? or is it pretty similar to the front installation? i ask because im curious about the rear pinion angle being in line with the drive shaft.. not sure i understand this.

 

just so that we're clear, when you say rpm, you mean when you put a load on your drive train, correct. i mean, you couldn't reproduce this shake at a stand still, right? if we're on the same page, this still points to a driveline being out of balance or maybe even a problem with your pinion. did you recently have gears installed?

 

correct. when you put a load on the drive train ie give it more gas the shake goes away. I can try the rpms at a stand still and see if i can repoduce it. this is a stock 07 jk i bought last year that came with a lift kit already installed. no gears have been changed.