So I noticed last night that the Driver side rear of my car is sunk. But I look and the suspension looks fine! It looks identical to the passenger rear strut. The front driverside is kinda lower but i assume that to be due to the back.

My friend and I checked and the springs are are very close to the same tension and the towers are not bent. What could it be? Thanks!

 

I had that happen on my passenger rear side, wheel was about 25% under the fender, and i had some rub. it happned just as i pulled in the driveway. I had one of the rear control arms just gave in and bent, I did not even notice it when I went under there, the first time.