Vibration/ humming?????????

[oompa83]

Last Friday my 06 Liberty began having a vibration from somewhere??? mainly occurs when deceleration and at almost all speed you can feel a slight vibration I had it on a lift and checked both wheel bearings. They are tight the noise/vibration couldn't be found while on the lift. "drove" in both 2wd and 4wd and no vibration only seems to occur when under a load inspected both drive shafts for a missing weights and checked ujoints both are tight. this is my first Jeep and im lost when it come to this please your input is appreciated

 

[Cardhu]

Try ujoint after a ride and feel if its hot. Should be ice cold. Mine went at 85 000 km.

Does the vib stop or minimize when your on the flat with cruise on?

 

[oompa83]

Its alot less at between 30-60 but you can still feel it but its mainly when i let off the gas and come to a stop then it gets really bad

 

[Cardhu]

U joints are cheap. Probably start there as what your describing sounds familiar.

Mine didn't have any movement in the shaft.

The rear flange is held on by 4 bolts and relatively quick to check. My rear joint was what went and can be checked without pulling out the boot at the back of the transfer case.

 

[Bundu Boy]

I had a similar problem with my KJ recently and it turned out to be the rear u-joints....

The mech called me in and showed me the u-joint at the rear diff. 3 points of the joint were cool after running, the 4th was hot.... it was seizing.... get that checked out....

I had the entire propshaft serviced and voila.... vibration gone.....

 

[oompa83]

Well i replaced the u joints today and the vibration is still there but I did notice that if I'm parked on an incline the jeep will roll down with it in drive. So now I'm starting to think that its coming from the torque converter. Anyone think I'm right??

 

[Habsrup]

90K on 05 Liberty....Ujoint on rear shaft at diff....started as a hum at low speeds and felt like some break pad sticking at a complete stop....(wasn't the breaks). Then started to feel a vibration intermittently on deceleration (felt like driving over the warning grooves on the hwy) without breaking from 30 - 40 mph to 0 mph including in neutral. For those who want to try this on their own (Cost is about 20 bucks per joint) and I only replaced the rear joint at the diff. BTW - its a lot easier if you have air tools...1) With my air gun it took 30 seconds to remove the 4 bolts.....2) cut the smaller boot strap at the transfer case. Move the shaft towards the Transfer Case by prying it a bit and it will drop....3) to replace the UJoint now that the shaft is out go on YouTube and find a video on how to remove and replace the Ujoint... there are plenty of videos...NOTE you will need a strap or black tie wrap to seal the boot back up when your placing the drive shaft back on the car... Also note its a good idea to use bolt lock liquid on the 4 bolts...If you have the tools and patience it will save you hundreds of dollars..Also if you do try this work safe...I jacked up the two rear wheels and placed the axle on 2 stands to give me more room to work..I also blocked my 2 front wheels in both directions with wheel wedges..Better safe than sorry...