Hey, I was driving down the highway and I hit some metal sign in the middle of the road, it went to work underneath the car and then went flopping down the road. Afterwards there was a lot of noise that wasn't previously there. I think its coming from the transmission. Do you guys know what that darn sign could have done? Oh yea I tried my best not to hit it, but I only made it down to about 55 before I tagged the thing! I got 



That would scare the crap out of me! I would say the best thing to do is just crawl under there and see if you can find any visual damage. Hate to say it, but most likely you will find some.