Sagging rear...

[Spades]

Just as the title implies, the tail end of my yaris is sagging. its not quite 3 years old yet, and it went from sitting a inch taller in the rear than the front, to where now the front has 1 more inch of wheel to fender gap than the rear.

the car isnt lowered and is riding on stock springs and struts. for a long time I had a coupe hundred pounds of subwoofers and audio junk that perched the load far into my sedans trunk. I recently removed that box and built a lighter weight one. the custom box moved the weight forwards and over the axle instead of part of the weight behind the axle. the new set up is about 90lbs, old was somewhere around 200lbs.

even with the new box, the car continues to sag. when new the car had insane amounts of body roll and handled like crap. I assumed it was because it was a cheap econo box. I know it isn't my imagination, because now the exhaust I installed is hitting on the bar linking the dependant suspension together.

i cant load any groceries or anything in the trunk, even 50 pounds will drop the car another inch.

has anyone else had this problem? the shocks arent leaking, so I am guessing springs at this point. I highly doubt toyota would offer to replace them under warranty, citing that normal wear and tear would have caused it.

I was fine with body roll and crappy handling, but the sagging is making me wonder if the car had a issue with springs or shocks all along. anyone else with this problem?