Could be a bunch of things...but the most likely is over torque on the UCAs/shock bushings/lack of lube.
Did you grease the zerks?
Use a torque wrench on the bolts?

_________________________
- TJ
2001 Xterra '03 VG33, SE 5 spd, 305/70/16's, Revolvers, UBSkidderz, Doubled AAL's, 3"SL/2"BL, winch/bumpers, skids, sliders, OBA, Snorkel, pine stripes....
Friends don't let friends drive stock.
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