I have a 2017 RAM 2500 6.4 HEMI. I wanted to coax more power and a performance sound out of it so I had a custom exhaust system built for it (a CAI system from K&N is sitting in my garage waiting for the next phase of my bolt on quest for maximizing the HEMI's power). The OEM pipe front to back is 3.5" and I couldn't see getting rid of virtually new and good quality OEM piping so I asked for the muffler to be replaced with a MagnaFlow performance muffler, remove the OEM resonator and put a custom 2 outlet slant cut stainless steel tip on it. I couldn't do a dual exhaust exit because of the tight surrounds of the coil sprung rear end so I only have the one pipe, front to back. To be sure I still had 3.5" from front to back the shop ordered up mandrel bent pipe with the muffler (stainless steel as well) and modified the tip I supplied to make sure there was nothing less than 3.5" anywhere in the system. This guy has done work for me before and does great work at very reasonable prices so I know he knows what he is doing (I got a custom built system for less than half the cost of a bolt on store bought system). I love the sound and noticeable performance but it seems louder at freeway speeds than I remember from other similar systems I have had; it almost has a drone to it). So all this being said to set the stage, I am thinking it is noisier because of the large 3.5" pipe, the performance flow thru 3.5" muffler and "no resonator", which I understand but wasn't expect to be that much difference from what I have experienced in the past.

I have a theoretical solution to tame things down some and that is the real crux of my question: Will exhaust heat wrap on the muffler and a short distance in front of and aft of the muffler contain some of the noise that may be emitting through the case of the muffler and pipe closest to the muffler? Since this is right under the cab I thought if there could be some containment that it would reduce the noise (heat is not the issue) from radiating into the cab (which I suspect is happening, at least somewhat) and quiet things down some in the cab as well as reduce the suspected droning affect. It kind of makes sense to me so does anyone out there in MOPAR land have any experience or an opinion on this?

I welcome your response, advice and input. Thanks in advance for your responses.