Hi i am new to forum. I have a brand new 2008 mega cab 1500 5.7 hemi when i get on a washboard road or go over small bumps i get a load banging sound. It sounds like a drive shaft hitting the floor board. I can't find any marks and neither can the dealer. Has any buddy else had this problem. Thanks

 

It could be the bed hitting the cab. That long of a truck has tons of leverage to flex the frame. Or if you have a hitch it could be that bouncing up and down in the reciever. Or in some instances it could be the hood hitting the fenders so just open the hood and raise those plastic bump stops.

 

I have a mega and the only time I heard a noise like that is when the bed bolts weren't tight. I had to get under the bed and tighten 4 of the bolts near the cab side of the bed for some reason. Other than that it shouldn't make any noise at all. good luck finding that one out. you might need to strap someone to the bottom and drive over some speed bumps.