2008 Volvo XC70 Creaking/groaning noise

The car makes a creaking/groaning noise when I make a right turn and occassionally when going over a small bump. The noise seems to be from the entire vehicle 'straining" or creaking, sounds like it is coming from underneath the vehicle. Weight distribution seems to make a difference, I weigh 130 lbs. And can hear the noise quite clearly but when my husband or son drives the vehicle they can hear the sound, but not loudly. The local Volvo dealership diagnosed the problem and installed two new shocks, but noise still there. Just bought the vehicle 2 weeks ago, Enterprise Car Sales is willing to pay for repairs if we can figure out the problem.