Weak Rear Suspension?

[CTM Nismo]

The 07 Altima I just got is really low in the back end. All I did was put my subs and amp back there, about ~80-100lbs or so. Way less then if a person or two were in the back seat. Before that it looked fine.
This picture is when I got it,


Ill post a pic tomorrow of how low it is now. There is barely enough room to fit my hand in between the wheel and fender. It looks like it was lowered about 1.5in or so.
Also, when going over even pretty small bumps, the rear end drops low enough to scrape pretty much every time unless I go slow as possible.

Is this normal for the suspension in these, or should I get it looked at?

[rcboy514]

I've noticed this on a lot of the sedans....seems weird, I would get it checked out.

[IBCoupe]

If you stand behind your car and push down on your trunk with a fair amount of force, does the back end bounce excessively?

[CTM Nismo]

Sorry, didnt have time to take another pic yet. Spent the free time I had doing the big3.

Havent tried pushing down on the rear yet. Will do tomorrow.

[CTM Nismo]

Cant see it too much from this angle, but its definitly a bit lower.

[Hollaitzwillie]

u know what i have the same problem. all i got in the trunk is my sub and the rear end drops atleast a inch 1/2. have u checked out the dealership?

[CTM Nismo]

I think its to do with the location of the seats/trunk/suspension. With the subs out and back seat full its fine because its between the wheels. But the subs in the trunk is 100lbs directly on top and behind the rear suspension. I got a new box thats wider and spreads the weight out better, so it only dropped about 3/4 of an inch now.