I thought it was meant to make things easier to disassemble when working on it, I'd be really surprised if the suspension was designed so anything could get damaged at full droop, that would just be a bad design practice.
Hi,That tool is not for hoisting or jacking,it is used for checking and or replacing the upper ball joint.It takes all of the weight off the the balljoint so you can check the freeplay.Chris
Is quite right that the tool is intended to be used in case of a ball joint replacement. But I use it always because it destroys the upper shock absorbers rubber. Maybe it's because I have the harder 429 coil springs. (They are really hard!) But do not think that's healthy for 351 c springs either.
Has also happened that the lower controll arm bushing has broken