Quote:

... Considering the car is "lowered" means the torsion bar may be under zero torque; however, the reverse loading from muliple bumps on the road may be the driving force for a fatigue fracture (essentially a reverse loading scenario).



While typing my previous reply the thought occured to me that the lower stance of the car might very well have something to do with this.

Here's my idea of what could also have caused, or at least helped it happen;
The bumpstops on the car get quite a workout because of all those damn speedbumps overhere, and I wouldn't be surprised that when the bumpstop hits the frame, any remaining downforce of the car will use the tires, but also the bumpstop and LCA as a fulcrum and this force will somewhat be transfered to the LCA's torsion bar socket. This could probably put a bending strain on the bushing, and the torsion bar on the other side.

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