88 xj.... annoying vibration from 65mph and up

[assterisk]

i have had a little annoying vibration since i owned this jeep.... my wife is forcing me to sell it, so now i have to try to figure it out.... what i know....
new tires....balanced, all ujoints and axles are tight, all diffs are topped off, and it has been aligned.... any help greatly appreciated.... dont want to lose a grand on the sale cause i cant figure this stupid vibration out....

 

[GSequoia]

Is it lifted? If so how much?

 

[assterisk]

it has an extra leaf in the rear.... the wheel wells measure 31"
but it has done this for as long as i have owned it.... even with a saggy rear end.... someone suggested a tweaked driveshaft.....
that ones kinda makin sense to me.... what do you think?

 

[keith haw]

If you figure it out let me know.. My 87 does the same thing. 3" Rancho lift and 31" tires... Tried balance on tires and pulled regreased u joints on rear.. no luck.

Keith

 

[assterisk]

GONNA REPLACE THE DRIVESHAFT THIS WEEKEND......
I'LL LET YOU KNOW.... SORRY ALL CAPS...