2011 Kubota RTV Muffler Heat Shield Noise

[DanielDD]

Hope someone has encountered this. I did an internet search and only came up with one thread that addressed this, but was not complete....

It is directly related to the muffler heat shield. I can remove the heat shield and the noise goes away. It is only at a certain RPM and I can replicate it regardless of whether it is in drive mode (L,M,H,R) or neutral. I drove around the farm with the heat shield off and it was perfect - except now the bed gets fairly hot, so I have to re-install the heat shield. All 4 screws that attach the heat shield to the muffler are intact and work well. I made sure they were all sufficiently tight, but this doesn't fix the problem. Seems to be a harmonic issue. I can rev it up at the point where the annoying rattle occurs and simultaneously apply pressure to the heat shield and it will stop. No part of the heat shield is touching the muffler other than the 4 attach points where the screws go.

Anybody had this issue with their diesel?

 

[pmsmechanic]

Use red/orange high temp silicone and apply to the screws when you reinstall the heat shield. That will take care of any looseness in the attaching points. If the rattling still persists then I would build a few silicone "bridges" in strategic spots to keep the shield from resonating. The silicone will be unaffected by the heat of the muffler so don't be reluctant to use as much as necessary. Temporary forms can be made out of masking tape to encourage the silicone to dry in desired areas.

 

[Paystar]

I had that problem with mine, but I just had to pull and bend mine up a bit and it solved that. Mine were touching.

Then I had to put an extra washer behind my Orange Aftermarket rear protection plate because it was doing the same.
And lastly, put a couple wraps of electrical tape on the tailgate pins to tighten it up.

 

[DanielDD]

I like the idea of the high temp silicone. I'll try that.

As far as bending the heat shield so it doesn't contact the muffler, I've already confirmed that is not the problem. It was originally bent, but I straightened it out. The result was that it didn't make any difference in the rattling...