HELP! Rattling/Grinding noise

[raider1]

My 06 F250 has started making a rattling/grinding noise. It started the day I had a Magnaflow turbo back exhaust installed. Took it back to installer and he said down pipe was hitting on something so he moved it over???? Anyway, the noise went away for about a week. Now it is back and worse. Sometimes it sounds like a rattle behind the dash and/or under the floor, and other times it sounds like a sort of grinding noise. Any ideas? Also noticed a thin cloud of white smoke coming out of exhaust today when idling but it went away after a couple of minutes. First time I've noticed it. I've had a Bullydog downloader on for about three months but have never had any issues until the exhaust was installed.

[sanclementian]

Im having the same issue with the vibration noise. And I also have a magna flow exhaust.

[97Beast]

Hmm don't know about the smoke, but i'm pretty sure that the rattling might be from the pipe hitting against the side of the transmission. My brother had this problem with his 01 7.3l. Try moving pipe around and if the problem reoccurs wrap the problem area of the pipe with some header wrap to act as a buffer.