I had same issue. With the beefed up a arms, there is barley enough room for nuts on the ball joints to go all way down. Check to see if on the bottom side of ball joints are tight. They tend to get slack in them. If so, the ball joint will push out. Check all points of ball joints. Should be able to just push on tire, and if looks like there is slack on spindles, need tighten. Use (lock tite) on the nuts of ball joints. Also, check your large nuts, that connect your a arms to bulk head. They tend to vibrate loss also. But not noticeable. Again, should be no slack in them. If none of that fix it, contact Travis at BD. He might have a better fix. Or might know what's going on.
I still have a slight inward on my passenger side also. Very slight. Not big issue. Not near as much as what you got. But if he has answer, let me know.
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Also, check you bulk head. Make sure it's mounted straight on frame. Can check your shocks also. If there is any kind of length adjustment. The nut can come loss. And change length on shock. Somehow, happened to me as well. Even though both ends are locked in place, the shaft, can freely spin, and turn it self out. Might need to take both shocks completely out, and compare.
Lock tite.
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