I just installed a 51 " Donaldson muffler and the truck sounds great but when I climb under neath the section from the down pipe to the muffler is vibrating. Is this normal ? If not any suggestion on what or how to fix it. Thanks.

 

Did you weld hangers onto the muffler? If so are there any other hanger sockets on the truck not being used? You could always add more.

 

You know I re-installed mine and im getting a slight rattle, I think its one of the band clamps or my tip, either way I cant believe I ever took this thing off, what a sweet muffler, no vibrations, no drone, and the truck is much smoother, its a slight bit laggier down low, but its worth it, is your hitting the crossmember at all? might need a bit of coaxing

 

My only complaint was the trashcan like vibrations I got from the muffler so I stuffed it with FG insulation, wrapped it with more FG and built another sheetmetal cover over that. I have a muffler in a muffler. And I still want it quieter! Craig

 

Is there a difference between the donaldson and nelson? I just picked up a 41" nelson. It is not as loud as I thought it was going to be.

 

I don't feel the vibration but I can see it when I'm underneath it. You can see a liitle vibration on the tail pipe too. I not ot concerned just since there is no noise and I can feel any vibration. Maybe I will add one more hanger. Thanks.

 

let me know if the extra hanger helps the vibration. Mine is doing the same thing.

 

Love my 40" Nelson too.

Here's a cross reference that's handy:
http://www.cumminsfiltration.com/pdf...s/LT32002D.pdf

 

I noticed the same thing on mine. It also did it when I had my dynomax muffler installed. I think its from not having the front exhaust/stock muffler hanger on. They also had to cut the front muffler hanger off when I installed the big donaldson 51. Another hanger in there would take it out, let us know how it goes.