What I had happen was that the stock bolts had enough clearance inside the joints that the latter could shiftfore & aft, eventually moving the bolts. The threads hogged out the several of the brackets on both sides, and took a toll on the mounting holes in the flex joint balls. The nuts never came loose. The 9/16"s upgrade on all of the lower 14mm joints and the track bars solved all that. Nothing ever shifts and there's been no further issues with the bracket wear.
'09 JKRU. 4" Teraflex long arm, Teraflex R44 housing, Teraflex / Fox Resis, Poly Performance skids, Nemesis Billy Rockers, Nemesis flares, 37" ATZ P3s on 17" 5x5.5" Trailready HDs, Spyntec hubs, Teraflex BBK, Mopar BBK master/booster, Superior front & Alloy USA rear axle shafts, CTMs, Reids, Synergy drag link & tie rod, WTOR hydro-boosted steering, 5.38s, TF Dual Rate front bar, TF bumpers, Warn Powerplant, Tom Woods shafts, AA xfer case cable, Kilby canister relo, RH4x4 cage.