first off, 2008 jk with 3in bds lift and 35 in tires and 3.73 gearing. ok so i posted a while back about taking the jeep from nc to ms. well i am on that trip right now with the family stopping along the way at different becahes (in pensacola, fl now) anyways, my jeep has been really great so far but once i get up to around 70 mph it starts to shake and shimmy to the point its noticable. what would be the cause of this? i was hoping something easy to fix like maybe needing to get the tires rebalanced. anyone know what might cause this shaking at certain speeds?? i looked at my tires really closely last night and didnt see any issues with the tires and they are wearing perfectly even it looks like. fast feedback is needed!! still have a 2 hour drive to our final destination!! thank guys!!

 

did you check the track bar (tightness and bushings)? wheel balance?

 

everything looks and feels fine. it rides somooth as can be until i get up to about 70mph and up. maybe im just being paranoid since ive never driven the jeep this far on the interstate and maybe it could just be the wind hitting the jeep but it makes me a little concerned. like i said, my tires have plenty of tread left on them and they are wearing very well and evenly on all tires. does anyone elses jeep shake on the interstate at high speeds?? the shift knob goes nuts shaking back and forth as well. i think once iget to biloxi, ms i am gonna have my tires tested for balance just to be sure. still more opinions are very welcomed!!!

 

looks and feels fine but did you put a torque wrench on it and make sure it is at least 125ftlbs

 

I would start with looking real close at and around the tires maybe rebalancing them wouldn't be a bad place to start.i would think your tires would shimmy before 70MPH though,but not always. then i would look at my driveshaft for any issues. most the time when it is speed related it's something with the wheels and tires. if you threw a weight off a wheel it wouldn't show tire wear but would shimmy.

 

My guess would be Tires.

 

wheel balance would be my first guess... take it back to where they were mounted and have them do it again.

if you have been wheeling lately... those rim weights can be broken or knocked off on the trail

 

where is the vibrating comming from?

 

My vote would also go with getting the wheels rebalanced. If the shimmy is felt in the steering wheel, the problem is more than likely comming from a front wheel. However if the shimmy is felt in the whole Jeep or seat of your pants the problem is in a rear wheel.
Hope you get it and make the driving experience as great as it shold be.

 

Almost sure it is the lift and tires. Stock Jeeps don't have this problem.

Sorry, that was inappropriate, good luck with it though.