OK, here's the problem in a nutshell. I have a 97 XJ with a Rubicon 3" spring over add-a-leaf suspension lift with 31/10.50 AT. The truck runs awesome, except for the loud rumble coming out of the back end. It really sounds the loudest at about 3000 rpm's or on the freeway at about 65 mph. But when you let off the gas it quiets down a ton. Some friends have described it as a vibration, I think it's more of a rumble it almost sounds like a metallic sound.
In my opinion the spring packs have also sagged quite a bit. I can't find any photos to confirm. That's more of an opinion. I replaced the u-joints on the rear drive shaft a couple weeks ago. Last weekend we decided to shim (2 1/2 degree shims) the rear diff to see that did anything. Neither did a thing.
So here I am back at square one looking for suggestions. My feeling is that it should not be this loud.
Does anyone have any suggestions or comments???
In my opinion the spring packs have also sagged quite a bit. I can't find any photos to confirm. That's more of an opinion. I replaced the u-joints on the rear drive shaft a couple weeks ago. Last weekend we decided to shim (2 1/2 degree shims) the rear diff to see that did anything. Neither did a thing.
So here I am back at square one looking for suggestions. My feeling is that it should not be this loud.
Does anyone have any suggestions or comments???