so i'm driving home saturday (about 370 mile trip one way) in my '07 X (build date november '06, bone stock performance/handling wise). when i start out everything seemed fine. most of the roads i'm taking are freeway (70 mph) or 2 lane highway (55 mph). maybe 100 miles in i start to notice a slight shake/vibration between 55 and 65 mph. nothing serious. i figured maybe a rear tire out of balance (since the vibration was not coming up through the steering wheel). by the time I got home, the whole jeep is just shaking a lot and there is a slight whine coming from the rear end at times. steering was not compromised much at all, so that leads me away from the front end, plus the whole jeep was shaking up and down, so that makes me think something with the rear end. Any thoughts? drive line, wheel bearings, differential? it was bad enough at the end where i was ready to pull over or was at least preparing myself for an emergency situation in case something broke while i was driving.

i've got a call into the dealer, so i'll be bringing it in soon, but wanted some outside opinions too. thanks.

 

mine shakes too around 65-75+. i do contribute this to getting the teraflex 2.5bb and 295/75/16 terra grapplers. what really causes the shaking? its bearable but it would be nice to get it gone.

 

it could be the pinions in the rear differential...or the axle..

how is the seal? anything leaking? have you tried jacking up the vehicle and removing the wheels and noticed anything?

oh yeah, and if the ride is shaking above 60 it's USUALLY out of balance tires. and yes, there are a LOT of techs out there who write off that they balanced the tires but indeed have not. also, oversized tires go out of balance all the time it seems (i actually work in a suspension, tire, and maint shop). try bringing them in and have them balanced. most tire retailers do it for free if you bought your tires from them!

 

Could be death wobble. My 07 JK had about 5,000 miles in March when this happened to me. Any small bump on the road would set it off between 55 mph and 70 mph. The cause was a broken shim shock and it was repaired under warranty. Google search "jeep death wobble" for more info...

 

thanks. the dealer has now had it for 2 full days (they didn't know anything at the end of day one and i haven't talked to them today). if it was just an out of balance tire, i'm sure i would've heard from them by now (god i hope so anyway).

as for dif, there was some dampness around the rear diff, but nothing ever dripped off it. i didn't have time to jack it up and take off the wheels to see what i could find. hopefully they will have some news when i call this evening.

 

so apparently one of the rear axle shafts bent. i called and ended up talking to a shop lackey real quick last night who told me it was the axle and that they ordered a new one. i'll get more details today (hopefully) from someone you has more of a clue (that's what i get for calling after most of the mechs have left for the day).