Hey guys. I have a 55 Bel Air 2 door hard top Sport Coupe and when I have passengers in the back seat and I hit a significant bump the car makes noises that sound like something is loose and banging around. When I turn up an incline on a slant the car makes rubbing noises. It doesn't do this when no one is in the back seat. I have replaced the shocks and it still does this. I have gotten under the car and searched for anything loose and everything seems to be tight. I thought it might be my tires rubbing from the extra weight and from the body shifting at an angle when going up an incline on a slant, (liking pulling into my driveway from the street) but I'm having a hard time determining if that's the case. I have 17" rims with TTIC 245/45 R17 95V tires on the rear. I have looked under the car in the wheel wells and can't see any sign of rubbing on the wheel wells or the tires. One of my passengers suggested it might be the springs in the rear seat but the noise sounds as if it's coming from under the car. Any advise and help is appreciated. Thanks in advance.