Did you just bolt to the rear cross member or have you tied that thing to the frame? The cross member itself is very weak so a frame tie in is highly recommended.
'91 YJ 4.O, Auto, Rr. D60 w/ 35 Spline Alloy USA Axles & Detriot Locker, Fr. D30 True-Trac, 4.56's, 4.5" Deaver Springs, Bilstein 5100's, 1" BL, Rubi Flares, 35x12.50 MT/R's on MT classic II's, Detroit Locker, Vanco Big Brakes, Booster & Master, Warn 9000XDI, York OBA, AA SYE & TW's DS's, Teraflex Belly Up, Rocker Guards...