I just installed a 12" dynomax bullet with a dump before my rear axle yesterday. My set-up is pacesetter l/t's, ory, and the 12" dumped bullet. When I am accelerating normally, around 2500 rpm my car starts vibrating TERRIBLY. It goes away around 2700 rpm. I know that dumps vibrate, but this is not the usual vibration. It is a hard vibration, like when your tires are worn out and you are driving at high speeds and it makes the car vibrate. It is really annoying, and I was wondering if anybody else had this problem? I also did not use my tranny mount on my y-pipe, could using this help out at all?

 

Has anyone else had this problem with dumps/true duals or am I the only one?

 

I found the source of the problem. My hanger. I cut it off and the vibrations went away. So I guess I gotta fab up another kind of hanger. I used one I got from an exhaust shop, but I guess I will try a different kind from autozone.