I've looked at the exhaust muffler replacement threads. I was wondering other than weight savings if this is worth the cost. hp gains? I then have to find a muffler shop that would do it.
Thanks
To me it was.Bed room cooler. Wrap the resonator and less heat on the AC components. Less bed room heat. Many post on it.
Hp, weight and temps are no worse....Testosterone is greatly improved! Especially in tunnels and overpasses.
Less weight, more Bling. Turbo spools up quicker. Frees up room in engine bay to mount something (?) else.
It's not rocket science. You could Do-It-Yerself. Only common hand tools required. Just kinda dirty removing the old 50 gallon muffler.
I did ours in my driveway. In Texas. In the middle of the Summer. :facepalm:
Resonator (https://www.foreforums.com/index.php?topic=27013.msg219731#msg219731)
Yes what Chuck said.. Current system is put together with band clamps so no cutting involved. Goes back with band clamps and no welding. Some of us repurpose existing muffler hanger to hang resonator. I used air ratchet for clamp nuts if you don't have air get you a battery operated gun. Way more than pay for it with labor savings.
I'm in the straight pipe club, turbo spools up much quicker, slight increase in fuel mileage, bed room way cooler. The bad neighbors in the campgrounds are not going to like you if you come in late and leave early, it talks to ya. I'm retired so I don't do anything early. Going down the highway the only time you can hear it is when you are next to something. It is a diy project. Like others said getting the old trash can out is the worst part
I was mostly after the bedroom heat issue, which it solved. Didn't have a before and after performance run. The side benefit is the possible storage behind the door that goes to nowhere.
Another resonator install (https://www.foreforums.com/index.php?topic=33817.msg309206#msg309206)
I can't say mine has anymore power but enough other benefits if it doesn't. The less bedroom heat is definitely noticeable.. Blasted original muffler is 3 times bigger than is necessary.. Like going from a big pot belly stove to a small one. Wrap it in wrap and mucho heat reduction.
That's the one I used. I wrapped it with DEI Titanium Exhaust Wrap where it goes past the A/C condenser.
My old muffler and tailpipe were completely rusted through and you could smell it in the bedroom, so I changed mine out of necessity. No idea on performance gains (little or none?), but it sounds glorious. I didn't want it too loud and this was just right for me.
Sounds like a bull instead of heifer ..Can't hear it from the seat but the people you pass can.
Very good. I'll add it to my list of upgrades. Probably go with the straight pipe and wrap for heat reduction at a minimum. Is the cummins a 4inch pipe? Looks like truckpipesUSA.com has all the hardware for it
Thanks much
Mines comes out 4" off the turbo, l just went 4" all the way out. And 4" stuff is way cheaper especially the chrome tail piece. We do a lot of boondocking so I turned the pipe to the side more so as to not stir the dust.
Dan, wait on this change until you have to do it. Especially if you are not doing it yourself. Some anecdotal improvement probably isn't worth doing it unless you need to. Some day I will do it but not yet. It makes your coach louder.
Think for some that is the idea.
I like the heat reduction the most. I've wrapped racing headers in the past with big heat reduction. I also know the turbo will spin easier so it helps with cool down. It will be on the long list for sure this fall or winter. I'll see how summer goes. I have plans for using it quite a bit at UTV rallies in Colorado and Utah
Have you had a chance to hear the difference between your straight pipe and a resonator set-up?
Tell me more about utv rallies please ?
No, I'm an old hot rodder and enjoy a louder exhaust if it helps. I figure I'll go back and add a resonator if needed. I'm leaning towards flex pipe for the entire muffler delete to the tail pipe
Lon , not really ever paid any attention. With that said it has to be under a load.
How loud is it in the bedroom while traveling down the road?
That's been the most frustrating thing about this Res/straight pipe changeover. Little more than subjective stuff and zilch for even a short cell phone recording of the before and after. could only find one video on a coach with the mod. That was just mashing the throttle in neutral. That registered 123 Db spl. Pretty loud. But it was a downward facing axle dump. That was an ISM 500.
On YouTube? I think I saw that a while back.
No fan boy report here. The facts as I see em:
I went from stock exhaust to the 5" in and out aero xl resonator. Routed with minimal bends, all of which are long sweeps.
Positive effects....by far, and absolutely not magical perception, the turbo spools up much faster. Two benefits are coach is much quicker off the line, and at higher altitudes, say city driving in Santa Fe, with faster turbo spool comes greatly reduced smoke on take off from stop lights .
Negative effects. Quite a bit louder. Don't find extra diesel sound appealing compared to a high perf gas mill. Basically, sick of hearing unruffled diesel pickups driven aggressively, starting to equate them with halfwit turtle races. But can be controlled by judicious application of go pedal. Ymmv.
Fuel mileage, bedroom heat, no idea.
Thanks Chuck. No street light rolling coal racing for my coach.
Next oil change before the southerly migration. I might have my shop guys throw on an aero resonator. If I do. I will try and make a video with the wife shadowing me on the road or hang her out the bedroom window to get a real sense of the sound between the two.
My feel for the resonator matches the quicker spool up.
On the m11 it let the motor lug down at lower rpms without the 3/4 throttle downshift.
Equal parts lower rolling resistance tires and lessening the massive hp loss from the fan system being fully on on a warmed up engine. Ridiculous.
60hp loss.
Now it acts like a real 11 liter Diesel engine. Weak overall power still but the large diesel feel is there. Was not there from stock.
My understanding of how a resonator works is that it removes the higher frequencies, but leaves the lower ones -- it shapes the sound to sound "better". Of course, that's subjective. I can tell you that my next door neighbor and some campers have complemented me on the sound. No complaints yet, but I'm idling up my neighborhood street or in the campgrounds. It'll be loud when you put your foot in it. But, so is my fully muffled F350.
It does sounds a lot like the too small muffler coal rollers. Whenever I hear a Dodge Cummins, I look around. The M11 is similar, but deeper.
IMHO, too loud. But, both my wife and my brother-in-law think it's just fine. My wife likes constant noise to sleep and my brother-in-law finds a diesel sound soothing. Going down the road, nobody has slept back there yet.
I can't tell you if there was a change because my stock muffler was shot when I bought the coach. However, my sense is that most of the sound is outside, by far. I wouldn't be surprised if bigdog measured little change in the bedroom.
Chuck, the comment about Santa Fe brought back some memories. We were camping in the Colorado mountains at about 9000 feet with my F350 and fifth wheel. To leave, you had to pull out of your site, drive downhill, and turn around in a loop at the base of the hill. That F350 belched smoke for quite a while (3-5 seconds?) until the wheels started moving. Never experienced that before or since. In normal circumstances (600 feet), even with the fifth wheel, it's not a smoker.
Man just wants a cooler bedroom..he will get it. I've never seen a motor home that put me in mind of a A Dodge Cummins with a Bully dog chip in it driven by a 25 yo and I get around.
I wonder if anybody who's done the resonator or straight pipe is unhappy with their decision and went back (or wanted to go back) to stock. That's probably a better diagnostic than "was it worth it?" or "what does it sound like?".
I am going to try to get sound level measurements in the bedroom while idling and cruising next time I'm out.
I think the cooler bedroom and faster turbo spooling are two sides of the same coin -- the exhaust is getting out and away from the vehicle faster with less resistance than from the muffler.
I would appreciate the measurements in the bedroom. The reason I ask is because we turned the closet into bunks for the kids and sometimes they go back there to take their naps (4 and 5). I wouldn't want them laying back there going deaf. The cooler temperatures would be awesome. Especially when you roll into Walmart at 8:00pm and go to bed at 9:00pm.
We have a resonator. I did the swap cuz it seemed (to me) like a fun project. I like the sound. I would not go back to stock.
If you do the mod, I personally don't believe you will see a large quantifiable change in bedroom temperature. I realize there are many anecdotal Forum stories about reduced temps in the bedroom, but I don't recall any actual scientific before-and-after measurements to prove this "fact".
I mean, just think about it. You have, especially in the U320, this massive lump of iron (the engine block) heated to around 180-220 degrees when going down the road. When you stop and park, all that hot metal radiates HEAT, which rises directly under the bedroom floor. Until the engine, turbocharger, transmission, and radiator (eventually) cool down, it is gonna be HOT in the engine compartment. No way around it.
Of course, removing the enormous stock muffler and replacing it with a small muffler (or no muffler) will certainly make some difference in how much heat rises below the bedroom. Fact: a BIG hot muffler stores/radiates more heat than a small hot muffler (or straight pipe).
But, consider the muffler heat radiation as a percentage of the overall total heat radiation from the whole engine/transmission assembly. How much difference will the muffler mod make in bedroom heat? No much, in my opinion. I would welcome hard evidence to the contrary.
I believe you could make a much bigger difference in bedroom heat by improving the quantity and quality of heat insulation between the engine compartment and the bedroom floor/bed platform. There are many Forum threads about this subject.
One might also consider the installation of some electric exhaust fans to suck heat out of the engine compartment after shutdown.
All of this, of course, is only my armchair opinion.
I agree with Chuck. I still have noticeable heat in the bedroom. The radiator and block are still there and hot.
I like the faster spooling and the sound, especially under bridges and in tunnels. I don't see any improvement in power or economy.
I'll keep my resonator.
The exhaust system can get to 800 degrees pretty easily. That's a lot of btu s .
Even when you change (or remove) the muffler, you still have the turbo in place. It gets pretty warm.
A turbo blanket and heat wrapping the exhaust pipes made a big difference in the bedroom temps for me. Yes, the engine block itself might be 200 deg but the turbo was glowing red hot. Most of that heat passes out of the tailpipe now and does not radiate into the engine bay. I have not changed my muffler.
The PO installed the resonator on my FT so I have no comparison. It's loud if you're outside and performs nicely.
One tip though, mine has a 5" tailpipe with a slight downward bend. On a dirt or gravel road you can see me coming for miles with the dust cloud it stirs up. I loosened the clamp and tried to roll it more to the side but no joy. It appears it has welded itself to the resonator. So I'll either go to a muffler shop or pull out the sawzall when I get home and cut some off since it sticks out 8" or so. Any idea how much is needed to not harm the fiberglass or paint?
Did a lot of dual Hayden trans cooler fan installs in the rear grilles on ORED's to remove heat from the engine bay after stopping. Some manual. Some auto
I used an air grinder and tried to follow the angle of the original tip. I was also able to angle it out to the side a bit. You might be able to use Corrosion X or a propane torch to free it up to rotate.
Folovier, If you are towing you might want to make sure that the diesel soot isn't going to cover your towed
Chris
DJ, while installing your bunkbeds system, it will help dramatically if you cover the bedroom area with DynaMat.. When I did that, it made a huge difference in noise and heat reduction.
Goes into my muffler shop the 22nd. I'll let you all know how it sounds and works. Straight pipe for now
Another vote for the straight pipe club.
As we began towing our jeep ( no toad prior) I got the bright idea that removing the stock muffler MIGHT add a horsepower or 2. I have to believe that it did.
Reason why is that prior to the muffler removal going northbound on I 5 Washington numerous times the 8.3 would shift down on 2 or 3 particular hills. After removing the muffler and going straight pipe only I found it no longer shifting down on those hills. And that was adding the jeep towed to the mix.
I was prepared to add the resonator if I found myself unhappy with the increased sound but so far we're ok with it. When cruising through a campground it's pretty ok,, unless there's a hill or even a speed bump to power over then we're making some racket.
Thanks Mark, doesn't that stuff go under the carpet? I didn't go too deep. I tried to leave it where I could put it all back if for some reason I have to.
I put a resonator on our 2000 that we just sold. My stock muffler was rusted out. It's louder in the bedroom but not deafening the couple of times I've been back there I'm typically in the driver seat so I don't get to hear. Our new to us coach came with a resonator and it's not that bad in the bedroom sound wise, yeah it's louder outside but I can't hear from the driver seat unless we go through a tunnel or under an overpass or next to a concrete barrier. I like the sound probably would never go back to a muffler.. May just be in my head but the bedroom seemed cooler when we would stop for the night...
For those of you thinking about switching to a resonator I put a Jones 50-50 XL on my 2000 it was about half the price of the aero turbine and from the research that I did it is identical inside and outside to the aero turbine so look into that and save a little money, I got mine for under 100 bucks delivered. Somebody with minimal mechanical skills can't do the change it's not that hard, buy the parts at a diesel parts shop or online. Needed a couple of hangers a 90*, a 45*, 3or4 band clamps and a little flex pipe to make it work. All was 5".. I was able to reuse the tip and turned it out to not stir up dust.
Keith
I was going to do it and your right it isn't a huge job although getting everything apart is always the tuff part but my muffler shop is 1 mile away, has a pit for motorhomes and will charge an hour labor plus parts. I gave into that offer. I ordered my heat wrap today on ebay and will wrap it from the elbow the entire distance past the cooler. Excited to hear the turbo more than anything. When I did this on my 97, 12 valve in my Chevy dually truck, it really freed up the turbo
For 1 hour labor I would let them do it too!!!
DJ, yes, I did put the DynaMat under the carpet. I was replacing the carpet, so at the same time, I covered the floor and bed pedestal with DynaMat in the bedroom. Then I removed all the Heat Blankets inside the engine area, covered it all with DynaMat including the bed cover, and then put the Heat Blankets back on. So I really have two layers of the DynaMat plus the heat blankets. My wife says it is much quieter than before, but the big change is the heat. After 8 hours on the road, when we park we get virtually zero heat coming into the bedroom now, before, the bedroom temp would rise at least 20 or more degrees when we parked.
Robert, did you use 5" pipe and resonator all the way out ?
Just don't kid yourself about the noise. When I was a parker during the Alaskan Motorcade it was obvious who had removed their mufflers. Be prepared for complaints in RV parks.
12 years with a 5" resonator after removing our muffler, 88,000 miles, hundreds of RV parks, never one comment Still prepared though!!
Well now unless your one of those folks that are nuisance idlers how long are you going to run your coach in the camp ground! Just saying.
I mostly dry camp and I consulted with the wildlife and they gave me an EPA sticker to go straight piped!!! Ha Ha.
At 700 ish rpm the straight pipe..... barely noticeable.
Same thing when you're piloting a F-16, you barely notice the sonic boom.
72db with original air conditioner running on high. Engine off.
87db at engine idle.
105db at 63MPH cruise.
So, pretty loud. Hearing protection is recommended above 85db, so once you start the engine, you're above that.
I'd be curious of the measurements by someone with a stock muffler. How much of that is engine noise that might be dampened by those heat blankets?
Thanks Rick. That is pretty loud. I haven't ever been back there while going down the road. I know it's pretty loud while idling. I do know that it makes a pretty good difference when you close the bed with the engine running. I hadn't thought about getting stock readings. We just made a trip to Louisiana too.
Maybe they would sleep longer with ear plugs in. 😁
Muffler, no muffler, resonator your choice. Yes it's loud but how long are you around someone under a load. Unless you are a chronic idler I can't imagine a problem in the neighborhood or camp grounds. Just saying. As always DWMYFG😎
Yup makes my Detroit sing😁👍
Ok. Took it for a highway and city drive yesterday and absolutely, NOT much louder and I can hear the turbo spool up and down. Very satisfied. With the weight savings alone, I can stock more beverages!!! ha ha
Good.. I may be the only one that's heard yours Andy like I heard it.. I was coming back to the site from downtown Quartzite in the car last Januarywhen you were leaving in your coach, met you on the 2 lane. Detroit was talking in a good way.
Chronic Idler, Thats a perfect name and I've met a few! You know the ones who crop dust the entire neighborhood with NO2 while performing their "Mandatory Engine Longevity Warm Up"..LOL
After I put on the resonator I could not hear a big difference from the drivers seat. When backing into my spot at Phoenix Raceway my brother was guiding me. Afterwards he said if that resonator didn't add 50 hp to put the muffler back on or give him earplugs next time.
And that's when you rev'd it up? >:D :))
I'd already shut it off. Maybe I'll get him next time.