been on this site now for 8-10 months, but just became a member. Just did a 4 inch lift on my 96 XJ and lowered the t-case 1 inch. Still getting a very small vibration at certain speeds. Can i drop the t-case another 1/2 inch...or will this open up another can of worms?

 

1.5" drop is the max I would go. Try checking your driveshaft angles. The pinion angle should be about 2 degrees down from the t-case output angle. Sometimes you can cure your vibes by adding a shim.

Save up for a SYE/driveshaft combo. Best cure for the vibes.

 

X2 on that

do you have a 4" or 4.5" lift? Did you install axle shims? i have the 4.5" lift with 6 degree shims and have very very slight vibes. something i can easily live with until i save up enough for an sye. if you dont have the shims, i would install them before dropping another 1/2"

 

I am going to say its a 4 inch lift. i did a s-10 pack in the rear and added 3.5' spacers in the front........center of the hub to flare is 21 1/4". i really dont see a big angle on the u joint at the rear pinion...i see more at the t-case end. I can add shims.....and the vibration isnt that bad...but i dont want to cause bigger problems. a 4 degree shim would be what?....1/4 inch thick down to nothing?

 

solved all problems by taking out the thick helper spring from the s-10 pack....cut the front spacers to match the 3/4 inch drop in the rear. rides like it used to now. Thanks guys!