Another great video.
This mod probably boosts the sound to a nice but tolerable level.
I'll admit, I like the quiet exhaust most of the time now.
How does it sound with empty interstate driving?

 

I can't hear the exhaust in the cab when on the freeway. There is no drone sound. I hear the tires first, then the engine, then my kids asking me if we're there yet. I am very pleased and surprised with an unexpected bonus. You know that high pressure PSHSHSHSHSHSHSHSH that the OEM exhaust makes when you're WOT? I use a freeway on-ramp that has a sound wall on the passenger side and up until Saturday it always sounded like a jet engine going up the ramp. The big Dynomax exhaust has completely removed that sound. I wasn't sure yesterday but today I tried it again and sure enough, no more PSHSHSHSHSHSHSH. The OEM exhaust is nearly silent at idle but makes a lot of noise at WOT. The Dynomax exhaust gives a low rumble at idle and pretty much through the RPM range. That's my take on it so far. Makes me wonder just how restrictive the OEM tail pipe and resonators are...

 

It's a big six inch stainless steel tip on a 5 inch pipe.

 

Not nearly as restrictive as the DPF itself. Relieving any restriction past the most restrictive part of the system is of little consequence to the overall ability of the engine to breath. I have yet to see a dyno graph (before & after exhaust install) that will prove me wrong.

 

Agreed. And the DPF is a variable restrictor depending upon how plugged it is. I have no illusions that I'm going to see any improvement in mileage or performance as a result of a post DPF adjustment. However, there is some calculable effect on airflow even post DPF. In theory, if the tailpipe was 30 feet long, it might actually create more resistance than the DPF itself. That is obviously not the case here as we're talking about 8 feet of pipe and two resonators. The only thing that I can concretely confirm is the elimination of the compressed air sound. At least there is no energy being wasted in an apparent compression occuring in the tailpipe.

Bottom line, this is just a theoretic topic. As you said, until someone comes out with a Dyno graph which shows OEM vs. Dynomax, the argument will remain academic and mostly useless.

It's still fun though...

 

Agreed 100%!

 

Another excellent video.. One sugestion, you need a lift in your garage!!!

 

Will you be able to use this new hardware if you decided to replace the other half of the exhaust hardware in the future?
(remove the DPF)

 

If it bolts to the DPF flange, it will bolt to the DPF delete pipe which is made to fit the factory exhaust.

 

Is there a way to hear the exhaust under load to see how it sounds now that the resonators are removed? Maybe mount it to the fender?

 

In the Ford manual they state several times that the venting in the stock tailpipe assembly is functional and needs to be kept clean and free of obstruction for proper operation of the exhaust system, particularly during high heat regen cycles.

It looks like the new exhaust doesn't have these perforations.

I'm new to diesels, but could that potentially be an issue?

 

You are right. Look at the video again an you'll notice vent holes on the angled portion of the stainless steel tip. Those vents serve the same function as the square/blocky OEM vents. The Dynomax folks figured that one out. The best part to see the vents is at about 4:53 in the video.

I'm looking forward to taking a temperature of the inner pipe and tip when a regen is in full swing. I have an infrared thermometer for the job.

 

I can't hear a thing, what is going on here!?!?

 

I just pulled into the garage after nearly completing a regen. It started when I was 500 feet from the house (as usual) so I drove an extra 10 minutes up to the highway and back to give it time to nearly complete. I wanted to take the temps on the new exhaust parts to see how hot everything is. So I grabbed my infrared thermometer out of the center console and went around the back of the truck only to find the batteries dead! This is where I jog into the house to get a new battery, tripping up the stairs and slamming my sorry face into the still locked door. My wife and kids, hearing the commotion in the garage, opened the door to find me with a bloody nose, crushed Big Gulp cup and soaked shirt and pants. They're asking me what happened and I'm yelling, Get a battery! Get a new 9V battery! They ignore me (as usual) and I jog dripping Diet Mountain Due through the house, to the office where the battery supply is. I find a new battery but I can't get the cover off the thermometer because my left hand is holding my nose and my right hand is too slippery from the Diet Mountain Dew. So I decide to just do a long inhale (hoping I can breathe in long enough to use my left hand) and switch the battery. I notice my middle daughter with her android phone now taking pictures saying, "This is so cool." I jog back to the garage and forget the Diet Mountain Dew soaked stairs and, you guessed it, ended up on a neat VCT tile floor in a heap. Fortunately there are only four stairs so the amount of energy I had picked up on the way down was less than that needed to break every bone in my body. At this point, my family showed some genuine concern for a few seconds until I got up and limped over to the back of the truck.

Ok, I just wanted you guys to know my dedication to the forum to provide good, accurate temperature data on the new exhaust.

External DPF temp - 190 degrees
External straight Dynomax spacer tube - 190 degrees
External tube temp just behind the rear tire - 178 degrees
External stainless steel tip temp - 78 degrees on forward side 102 degrees on the back side. (I think the polished surface did not allow a proper reading because it was too hot to touch)
Internal temperature of the tip - 280 degrees
Internal temp of the 5 inch tube inside of the tip - 380 degrees.

So clearly the outside exhaust tube walls are a couple hundred degrees cooler than the inside of the tube. This is likely due to the cold outside temperatures to start with and the normal cooling that happens when air is passing over it.

So there you have it. I never did measure the temps on the OEM exhaust so I have no comparison. Someone else needs to do that but I recommend you check the battery in your thermometer before you start.

 

Epic. Omg I hope your ok. But please post pics your Daughter took. Rotflmbo.