Chenzo

Hello to all, I've gone through the posts to see if I can figure this out before asking, but no go. I have a noise coming from the passenger rear side in the back that sounds like the sound that you get when you put a baseball card in the spokes of a bike wheel. The sound is deeper than a card but the noise is proportional to the speed. I noticed it while backing down my drive in neurtral. Lately it has gotten much worse and I notice that it increases with a load on it. I have not been able check it yet because of work. Any help and or links would be helpfull. Thanks in advance.