Suspension Noise problems of the 2011 Honda Pilot

I have had my 2011 Honda Pilot at the dealership (greg may Honda in waco, texas) 5 times for suspension problems and they yet have found the problem. It is making bottoming out sounds on white rock roads that can be heard and felt through the floor. Almost to the point of jarring passengers. I have had both rear trailing arms replaced at which did not fix the problem. I suggested to them maybe shocks. But they refused to replace them. I am at my whits end with this problem. I fear that eventually something is going to break and cause an accident. The trailing arms bolts are made of rubber which does not look safe to me. I just purchased this vehicle in July and have had problems ever since then. Please help. [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).