I have wanted to put a better muffler on my DX Mule but dealer said it might affect the 3 year warranty. Since it is now out of warranty I am ready to see if there is something I can do to quiet down this beast. If you have been able to install a muffler on any diesel UTV that made it quieter than the factory muffler did I'd like to hear about it.

I put a small car muffler on a Kubota RTV 900 and it helped quite a bit. I also put one of those heavy rubber horse mats in the bed and that also helped.

Thanks don K! Already did the mat thing. I thought about trying to put a tractor muffler on it but that would be sort of odd to fit as the factory muffler is short and fat.

I have a 18 model Mule Diesel and i called dealer about the warrenty if i put car muffler on it and he said no problem.

The noise from my Mule Diesel sounds like pure engine noise, not exhaust noise.

If you replace the muffler and it helps please advise as to what particular muffler you used.

I don't know how it compares to what you have, but on one of our Mules (4010) diesel, the air intake is directly behind your head and the noise is from the intake, not the exhaust. On my Kubota, I just close the door and it's gone.