When I runover a small to medium size bump/manhole/ road seam etc.. the front end is very smooth but the back end sounds like and acts like it bottoms out with a thud and sometimes the back end feels like it kicks up. I have also noticed the back end almost jump to teh the side when I hit a overcrossing seam in a tight turn today. Has anyone else experienced this? I have the SL FWD. Has anyone looked into aftermarket rear shocks that would help?