I will reinforce this...I used the MBRP muffler, not resonator. I don't know which is quieter as I've not heard the resonator. However the muffler is advertised to be quieter and is longer so I bought that. I have the longest 4" flow through muffler that will fit under the truck before you have to relocate hangers to hang the exhaust. So if you want quieter than mine, I'd encourage you to leave the DPF in place...

 

Yeah, I've been looking at exhausts. How long a muffler were you able to fit? I was actually about to pick up the phone to MBRP and talk to them about it. I haven't been able to find much off the shelf, but there is this from MBRP MBRP Performance Exhaust and this from Magnaflow: The Official Site of MagnaFlow Diesel Exhaust Products / 7in. Round Body Diesel Mufflers while SPE seems to offer a complete package, but with no info on what specific muffler they're using: Mbrp 4” Down-pipe Back No Bungs W Muffler T409 - Mbrc6262409 - Mbrp - Exhaust - Ford 6 7L - by

The problem is that all these aftermarket muffler people seem to think anyone looking at their stuff is looking for "hey look at me!" tone or some sort of "performance gains" exhaust system.

I'll give them a call, see what they say.

 

I have the FloPro Downpipe Back Dual System which has the delete pipe straight through. I bought the largest diesel muffler from FloPro and cut it into the delete pipe (23" Diesel 8" round straight through (no baffle) muffler - perforated core/ fiberglass packed). My truck is almost as quiet as stock until you put your foot into it. I tow a heavy 5er and it isn't that noticeable in the cab because of the low RPMs that the 6.7 makes power at until you take it down a couple gears on long grades. My wife still thinks it is quieter than my 2005 F250 gas truck with the FloPro exhaust I had on it.

I'm not a fan of straight piped diesel trucks (no muffler) and this setup sounds great when you push the throttle but not annoying. I appreciate the current H&S tune that limits the smoke until I open it up and even then it isn't bad. It still keeps the treehuggers off of your back since my truck blows less black smoke than a stock 6.0L did.

 

Note the hanger IMMEDIATELY to the Left of the muffler.

Note the hanger almost immediately to the right of the clamp? It's hard to see, but there is only an inch more room. Nevermind the bent skid plate...I use my truck off road often

The muffler that I have is 24" long plus a 3" flange on each end for a total of 30". 31" is absolutely the max and you would have to change the clamp style if you went the 31". I like band clamps that I used and wouldn't go smaller.

 

That's excellent info, guys. Thanks!

I'll be honest, I would probably be perfectly fine simply draining the DPF tank, shutting off the SCR, shutting off the EGR, and just physically knocking the DPF out of the factory rocketship and leaving it looking 100% stock from the outside. Is that even possible? I know people used to knock the center out of their catalytic converters; could you do that to the DPF?

Anyway, just to share what I've been told on the phone, I talked to both MBRP and to SPE (Snyder). I explained that I was perfectly happy keeping the stock stuff from the DPF back, but I wanted to keep things nice and quiet. MBRP recommended the QuietTone universal diesel muffler, possibly with the addition of a resonator, though I'm hoping the factory resonator should be plenty.

MBRP is terrible about posting technical data on their site, but they were able to tell me on the phone that the M1004A or M1004S (aluminized vs stainless) 4" inlet/outlet QuietTone is a 24" muffler that's 30" overall with a 6" diameter body. I'm not sure exactly which MBRP muffler you have, Savage, but based on the info you shared it sounds like this one will fit juuuust right

I talked to Amy and another guy (I forget his name) at SPE, and they were extremely friendly and helpful. Amy was able to answer almost all of my questions, but she handed me to the guy to talk about the delete pipe and so forth. He voluntarily crawl under a truck in their shop to look at a rig basically identical to mine, owned by "an older gentleman" as they put it, who had the Flo-Pro delete pipe with their own Flo-Pro muffler and nothing else changed. Apparently he was happy with the resulting sound and volume. In fact, he said the man and his wife both had trucks and both were deleted, but she got the down-pipe back with muffler and he got just the delete pipe at first and had come back to get the muffler installed because he liked her setup with muffler better.

He said that if I wanted to order just the delete pipe there should be enough room to cut a muffler into it later if I decided that's what I wanted to do. So Amy's pricing out the 4" Flo-Pro delete pipe (no bungs) and the MBRP muffler. I'll probably start with the delete pipe alone, keeping the factory resonator, and feel it out from there.

Now, one additional piece of info, after talking to the folks at SPE. I can confirm that the MiniMaxx (unlocked/race/offroad) can electronically shut off the EGR. No blocking plates necessary. You won't be able to get pyro/EGT data until you at least remove the pipe and install the blocking plates (one with a bung), but for those of us planning to stay at or very near stock and only rarely ever push their rigs to the limit towing overweight up a long grade or whatever, the EGT probe is not really necessary. The cool thing is you can always go back later and install the blocking plates, install a probe, remove the whole EGR, etc.

 

I have the M91031 T409 Stainless...I thought I posted that (sorry, I didn't). It is not the same as what you posted. It's similar though. Hopefully that one will be the perfect sound for you. I'm pretty happy with the one I have on the truck.

 

I don't know if I would want to punch a hole through the DPF. It's expensive and needed to restore it back to stock and I have no need to do so (no emission testing). Therefore I havn't researched it, but I know it would be more than just buying a delete pipe if you had to restore the DPF to working.

I feel electronically shutting off the EGR is asking for trouble. I realize that's a paranoid former 6.0L owner talking, but I don't trust it. I want it physically blocked off so when I remove the plates, I know it should be fine. You do what you want to do with your truck...the logic is on your side, not mine. Block off plates and the temp probe aren't optional in my mind.

 

Ah, so it looks like your muffler is basically the same except the one they pointed me to is a significantly quieter (10db allegedly...remember decibels are on a logarithmic scale) chambered/baffled design. Out of curiosity, do you know if you're is a straight-through design? If you pull it out of the box and hold it up to your eye, could you see right through it?

As far as the electronic EGR shutoff, there's already a valve to block off the EGR. If the valve is closed, blocking off the EGR, then what exactly could go wrong? Am I missing something? It seems like the absolute worst case scenario is that a little bit of exhaust gas might leak around it. If that's all it is, and the EGR system is still intact (just not being worked), then there won't be anything to cool down, nothing really to go wrong. The folks at SPE sell several different blocking plates and EGR removal solutions, but even they said don't worry about it if you don't want to unless you need pyro readouts.

As far as knocking out the DPF, I'm going to call a recycling center and ask what they're paying for them. That'll help me figure out if I might want to knock it out (or remove it from the housing entirely if possible) and just buy another one some day down the line if I have to for some reason, from someone else who deleted and is getting rid of it. I don't have emissions testing to worry about, at least not at the moment, so it's not like i have to set it back to stock every year. Plus, if I'm being honest, this is south Texas. You can get an inspection sticker on anything if you know the right people, and there are plenty of the right people out there.

 

I was under the impresstion that the entire EGR cooler had to be removed. but just taking the one pipe with the two block plates and EGT sensor will suffice as EGR delete? The EGR cooler itself wont clog correct?

 

Nope, the pipe going to it will be gone (no exhaust entering it) and blocked off with the 2 plates

 

You don't have to remove ANYTHING. There's already a valve from the factory to control exhaust gasses. Beyond that, you can install only blocking plates, removing only the EGR pipe. Beyond that, you can remove the EGR cooler itself, all of it, still using blocking plates of course. Why would the EGR cooler clog if there's nothing passing through it? Even if it were clogged, would you even notice? You could fill the whole thing with JB Weld or silly putty, and it wouldn't matter, because there are no exhaust gasses returning through it.

 

My muffler was straight through design all the way. I was told the a new DPF would cost over $3500 is the reason I made the comment that I'd sooner sell it than knock a hole in it. I've seen used ones with 50k miles on them go for $700 on Craigslist and they are gone in hours.

 

If you want to trust one valve, go for it. . I guess you don't tow and need to know your EGTS?

 

Is there any evidence to suggest that the EGR valve in the 6.7L is not trustworthy? Mine hasn't given me any trouble so far, and as far as I know there are no known or widespread issues with it. Moreover, is there any reason to believe that even if it were to fail partially or even fully open (never heard of such a thing) that the EGR cooler finally having something to do after all this time would necessarily be a bad thing?

I can't know my EGT's from the factory. If I'm keeping the tune stock, why would I need to know, unless I'm pulling ridiculous loads up steep grades over long distances? Even then I'm not sure how important it would need to be. The most stressful load I've pulled is ~17k lbs at 80 mph with much of that unaerodynamic load (Jeeps) up in the air stream. Yet I haven't had any engine meltdowns due to extreme temps. So why would I need to know them? And if the expert at SPE who makes money by selling these things brushed it off as not a big deal, I can't imagine it would be a big deal unless there's something I'm missing--which is certainly possible. Educate me

I just want to drive and use the truck like I do already, in 100% virgin stock form. I'm not looking to roll coal, lay down hundred-yard parallel rubber stripes, pull sleds in competitions, or pull 30k lbs of hay up a mountain. I don't really plan on running the MiniMaxx in gauge mode for that matter, either, so there wouldn't be anything to monitor. I have no reason to believe that exhaust gas temps during normal usage will be a concern, especially when eliminating EGR from the equation. That said, if I do change my mind, it's a fairly easy fix.

 

Yeah, that's all part of the decision making process. Swapping in a delete pipe requires some effort and a little expense, with the downside of not passing a visual inspection if for some unknown reason someone decided to look. I could sell it if there were people looking for it and recoup that relatively minor expense, or I could keep it, in which case it's this big part taking up space in my garage just in the off chance I might one day want it for something. On other hand, I could sell it now and then buy another one later on down the road (and take my chances in case there's something wrong with it). Or I could avoid all the expense and take out the DPF media, leaving the stock-looking setup underneath, disabling the rest of it electronically. I could still sell the SCR part later, I guess. That would also eliminate the possibility of adding a muffler to the system if the stock resonator isn't enough to satisfy me.

So, upsides and downsides. I haven't made any firm decisions yet

For reference, it looks like Tousley sells the whole rocket ship new for $2,300. While they have a call-out for it, it doesn't look like they sell the DPF separately. That makes sense, because I think the DPF is welded in, isn't it?

http://parts.autonationfordwhitebear...iagram=ME11340