XRAY - Model racing cars

I have been going through a few knuckles on the right hand side. Mostly due to the screw holding the cvd to axle keeps coming loose and ripping apart the inside of knuckle, just maint I guess with blue loctite. But this time the screw holding the turn buckle balljoint to c-hub keeps coming loose. I have tried replacing the knuckle and sometimes it holds, but other other times lately looses it's tightness. The bottom screw holding c-hub is fine and holds it tightness, not sure if explaining correctly. Any advice??

I've never had a problem with the CVD setscrew/grubscrew backing out, and I don't even locktite it. I have had problems with the upper upright and knuckle screws backing out. I fixed them both by a) crashing less and b) installing the longest screw that will fit. I have a selection of screws in 2mm increments (XRAY sells them), and I fit whichever is longest without touching the axle.