Steering Column problems of the 2006 Lexus GS300

I purchased my 06 Lexus Gs300 last year around may of 2008, from the day that I took the vehicle home, all I ever experiencing difficulties of problems. The first couple months of owning the vehicle, I heard a really big clunking noise coming from the engine bay, it appears to be some kind of cam gear grinding, I took it to Lexus of reno to have it fix not once but twice with the same problem, not to mention the steering wheel column also make grinding noises, I'd address this to the mechanic at Lexus and they wouldn't acknowledge my complaint. Today is August 19 2009 the trunk of my car wouldn't open from the remote control or the trunk opener from the inside of the vehicle. This is very inconvenient, it took me 60 miles or more coming back and forth every couple months to get the something fix.