Wanted: Performance Exhaust without the DRONE

[GaryCarter]

Hello, all. I'm posting this in the towing & hauling forum because I want to hear if anyone's found an exhaust upgrade that works for towing without the blasted drone that comes in just above 2,000 rpm.

This is the second Cummins I've owned (second gen and current 2005) and both times I've struggled with the drone after "improving" the exhaust. I posted here because I think what's tolerable for street driving or fun around town is a whole different thing than what's acceptable running all day on the superslab with a load behind.



So far I've installed and removed the muffler eliminator. Now running the MBRP duals. The cat remains. While the MBRP is a lot quieter OUTSIDE the truck it's not a great deal better around 2200 rpm with the throttle at 1/2 or more.

This drone thing seems to either happen only on specific trucks, or perhaps some drivers are not bothered by it? Others drive with the same exhaust and report no drone?



If anyone has good things to report about their exhaust mods on a 2004. 5 or later while towing and hitting that common 'noisy' spot just over 2,000 rpm, let's hear about it!

I'm good for about one more trial exhaust, then it's back to stock if I can't kill this drone any other way.



TIA

Gary



PS- it's a short bed QC.

 

[Cattletrkr]

I have a 4" glasspack from Heartthrob Exhaust. It's identical to any of the 4" "flow thru/straight thru" mufflers you'll get from anybody. They call them mufflers, but they're glasspacks. Any such muffler will give you a drone when towing. No way around it.



Dad's '03 has a short IMCO muffler and a huge Nelson behind it. Worse than mine. After we installed the Nelson, I saw pics of the innards of a Donaldson. That might not drone 'cause the baffles are different. There are threads w/part# in the 3rd gen forum if you search for donaldson.



That's about the best I can do. Good luck. If you do find something, let me know.

 

[Reb.B]

in the 04. 5 and above the stock exhaust is sufficient until 7-800 HP or more. JUst remove the cat and be done if you don't want drone.

 

[CMcDonald]

I have the Silverline Duals on mine. What I did was add a 20 inch Magnaflow just before the resonator. Now mine is the 04 with 4:10 gears. I had the problem around 70 mph which is near the 2000 rpm as I recall. The drone is gone and it still sounds good on the outside. Hope this helps.

 

[Fireman]

Gary,



I didn't have a CAT to deal with, but I found that a small straight through muffler on the end of the head pipe tamed the drone from my 4" system with a straight through muffler in the stock position. It didn't seem to affect the performance or EGT adversly.



Fireman

 

[dieselshu]

Exhaust

Give Rip a call at Sourceautomotive he should be able to hook you up with the right setup.



Dave

 

[RonCar]

Any such muffler will give you a drone when towing. No way around it.

Not true in my case, I have the MBRP Cat back with the Cat test-pipe and have no drone at any RPM...

 

[Mtngoat]

I have a Rip Rook 4" system in my truck, I don't get the drone till about 80mph, so its not a problem. Talk to him, he can probably help you out. He was very helpful to me on the phone. .

Robin

 

[GaryCarter]

Well, there doesn't seem to be more than one supporter for any one solution. I'm not convinced that the drone is consistent from truck to truck- I had more than one response before this thread suggesting the MBRP I have now. Either some trucks drone and some don't- or some drivers hear it and some don't.

Last truck I had the 4" JRE. It was pretty good all around, but still had that drone just past 2k.

What about the big names like Banks? Any Banks drivers out there?

I'm going to give it some time, but if I don't find a consensus on a reliable solution then it's back to stock before the next two week road trip!



Gary

 

[foolkiller]

i'm currently running the banks monster system. it drones too much for me. it's coming out as soon as its replacement comes in.



i've read from others who say it doesn't drone.



bet that helps a bunch. i'll post results out of tdr duties..... but it's been posted before

 

[Forrest Nearing]

ditch the cat... it'll help the resonance...



replace it w/ a big resonator

 

[NoSeeUm]

I run the Banks Monster Exhaust and I had the dreaded drone, but I just got rid of it. I installed a Flowmaster muffler just upstream of the existing Banks muffler.



The existing stock resonator was installed about 12. 5 inches ahead of the stock muffler and this is where I installed the Flowmaster. I don't know what the trick is. Wether it was the added effect of the Flowmaster or just the position in the exhaust pipe.



Oddly, I don't really care what the reason is. The drone is gone and I am happy.



Jim

 

[Forrest Nearing]

Jim, if you replace that flowmaster with a muffler/resonator designed for a turbo application, the turbo will spool up and cool down quicker.



hth,



Forrest

 

[MJG]

Silent Might worked on my 05

I removed the stock muffler (left the cat) on the 4 inch stock exhaust. With nothin' but the cat, the drone was ridiculously loud from about 1800-2500 RPM. Around town it wasn’t bad since the engine is loafing anyway, but highway driving was miserable. I wasn’t ready to give up and reinstall the stock muffler yet though. (Sure, the stock one is fine, but there’s no fun in giving up that easily . )



Installed a MBRP diesel resonator (a pretty short straight-through glasspack), but there was no noticeable improvement.



Next, a Silent Might from ROKK tech (http://www.rokktech.com/). The current setup is:



Cat: same as it ever was.

MBRP resonator: left where it went in—right after the cat.

Silent Might—squeezed in as close to the MBRP resonator as I could get, and the distal end of the Silent Might is angled up to meet the bend over the rear axle.



Result? The Silent Might did the trick— with the MBRP ahead of it, it’s quieter than the stock muffler at highway speeds (75mph in AZ—G56 transmission and all).



Now I can talk on the phone, listen to XM radio, etc. without thinking about the exhaust noise. The Silent Might is a pretty interesting design—a 48” long 4” diameter tube inside of a 9” diameter tube. No holes almost the entire length of the straight, 48" long inner-tube—just a few square card-sized holes at the distal end that vent into the BIG outer 9” diameter housing. (Tuned expansion chamber-- who knows?)



However it works though, the main thing is that I like it a lot more than the stock muffler—it is a smooth, straight-through exhaust that sounds better around town, and is fairly quiet down the highway.



Maybe it’s just the engine breaking in, but after ~1,800 RPM the engine power ramps up very quickly and smooth right up to redline. No other engine tweaks-- I’d have to say that this particular 05 CTD seems to run just right.



Picture: MBRP resonator on the right, followed by the 30-gallon :-laf Silent Might.

 

[Forrest Nearing]

you wanna feel that turbo spool up? ditch that cat!!!!

 

[4xquadrod]

Well, there doesn't seem to be more than one supporter for any one solution. I'm not convinced that the drone is consistent from truck to truck- I had more than one response before this thread suggesting the MBRP I have now. Either some trucks drone and some don't- or some drivers hear it and some don't.
Last truck I had the 4" JRE. It was pretty good all around, but still had that drone just past 2k.
What about the big names like Banks? Any Banks drivers out there?
I'm going to give it some time, but if I don't find a consensus on a reliable solution then it's back to stock before the next two week road trip!

Gary

I am convinced that people have different ranges or tolerences with sounds and audible squeeks etc. I have a bud that cannot hear or feel a drone. In his truck he has a squeeky rattle sound that drives me nuts and he cannnot hear it. I guess there are varying degress of hearing loss and ranges.

 

[keimmmo]

Personally, I run gutted stock mufflers on both of my trucks. I have ZERO drone at any speed, throttle, or load! They have a slightly different tone than stock, but they are not a bit louder than stock! I am an old muffler shop owner, so I have worked on exhaust systems for years. The secret is to remove the reverse flow tubes inside the muffler while leaving the silencing chambers. It will flow virtually like a straight pipe without the noise.



I have written instructions for the '92 and '01. 5. The basic information will apply to ANY muffler. Send me a PM with an e-mail address and I will send a copy to anyone who is interested.



Steve Keim

 

[Bugracing]

Steve;



you would not happen to have any pictures of your muffler's internals?

 

[STEVEBROOKS]

MJG,

Have you towed with your truck with your exhaust set-up? I'm very interested to know how your truck does under a load of approx 10K at approx 1800-2000 rpms.



Thanks,

Steve

 

[NoSeeUm]

Jim, if you replace that flowmaster with a muffler/resonator designed for a turbo application, the turbo will spool up and cool down quicker.



hth,



Forrest

Got a link to a likely resonator and/or supplier? Not really a common item around these parts. Nor have I been able to find one via internet stampeding.



Thanks;

Jim