what is the exact name/function of that square rubber bushing thing on the top of the control arm on the end opposite the spring? I think it might be some kind of rebounder to help prevent the suspension from bottoming out and smacking against the undercarriage. Mines cracked and its rprobably from a previous bottoming out and was never replaced except I don't know what its called to buy a new part. Any help will be appreciated.

 

Its called a "Bump Stop"

 

thanks. i'd rather sound like an idiot here than in the parts dept.