My 2005 SRT 6 Coupe had a fluttering noise at about 40 + mph...checked all plastic parts, wheel well, suspension parts...nothing lose...continued to drive and got much worse...now there is a clunking noise almost immediately when I get up to 5 mph..feels like the clunking noise is right underneath me....metal clunking for sure....no vibration in transmission or steering...feels like drive line??? U joint maybe...very odd. I have looked at everything that I can see under the car and nothing looks loose...help...any suggestions of what this might be are welcome....thanks in advance.