1999 cherokee sport
113k org miles 4x4
totally stock

It has a roar -vi bration starting at 65 mph gets louder with speed only at 65+ tracks strait as an arrow
I would guess from past experience it feels like a tire out of balance or possible bearing

I have

rotated brand new tires rebalanced... Had same problem with old tires

removed front ds completely
new upper and lower control arms
new brakes n disc
new rear ujoints balanced ds
new tranny mount
new unit bearings (old ones looked fine)
new fluids in axle xcase

I am stumped! I have checked alignment both professionally and me checking everythn is on.
Help. What else could it be?
Could bad shocks cause? track bar seems fine could it be to tight ?
thoughts?

 

Shocks wouldn't be the issue, but you could take them out and drive without them to make sure....

You can check your motor mounts as well....they could be doing something funny? It sounds like it would be something along the lines of a bad bearing somewhere.....

 

What do your front axle u-joints look like? Front and rear diff fluid?
Does the noise/vibration change if you pop into neutral at 65 and let the motor idle?
Any change if you turn slightly left or right?

 

Ok took Radi's advice.
(front driveshaft is still out)

I put transfer case in 4 hi and took up to 70 mph and basically no vibration or roar 95% + gone! Put back in 2wd at 70 still there. I would think that would eliminate front end - rear end -and leave just transfer case? Any thoughts?
Thanks

Jacksonbase
Actually no new fluid in t case just added more dexiii

 

Did you check your TS fluid level?

 

Transmission fluid level is good. Fluid is clean. I did drain xcase and replaced fluid. It was dark/brown. After running up and down road at 70 problem is still there but again incremetally better. It only starts at 65! It still feels like an out of balance wheel. I may rotate new tires one more time. I am about to give up.