2nd Gen Non-Engine/Transmission Help, Dreaded Drone!!

[dzlcrayz]

What is the best way to eliminate the drone that occurs at ~ 1800-2200 rpms? I just had a 4inch exhaust installed & I love it , but the drone gets to be too much on long trips, especially when you drive 70-75mph everywhere and the truck is in that rpm range at that speed. I thought I read about someone adding a second muffler What is the cure, other than going back to stock? (NOT) If it is an additional muffler, what type would be the best? Thanks in advance.

 

[kluther]

i had a bad drone with my 4 inch ex. i reinstalled my resonater and my wife will ride in the truck again. who's ex system do you have?i have banks and when i complained about it they sent me a 4 inch resonater free of charge. ken

 

[Chipstien]

I think I read that if you weld angle iron along the top of the exhaust it will get rid of the noise.

 

[Jim Fulmer]

I too had the 2200 RPM drone with my 4" and hated it, I know have a home built 5" turbo to tail with only a resonator right before the rear axle and have no drone at speed, the only thing I have is a rumble at 1400 RPM but it's a tone rumble and not a drone. At any higher speed and on the road it is really quiet but not stock, someone said at the Kerrville rally that it was quiet at 100 MPH as I went past



Jim

 

[n7gxz]

Something that I tried was to take some header wrap and wrap the down pipe and that took a lot of the ring out of my 4" system.



Kevin

 

[redneckdr]

drone

i have a "homemade" 4" system with a Goerlich's big truck muffler, straight through (no resonator). no drone. nice deep tone. sounds a lot like a straight pipe under acceleration. , and at idle. just not so loud or drone at cruis.

 

[BigMo]

Originally posted by Jim Fulmer

. . . have a home built 5" turbo to tail with only a resonator right before the rear axle . . .

Jim

Jim, can you elaborate on your custom exhaust? I talked with the local NAPA TRUCK parts store and they said they have all the tubing and bends I need to fab one up. However, my mechanic said it might be cheaper and "safer" to go with an aftermarket vendor.



Where did you start your exhaust, i. e. , at the turbo or did you use a 4 inch downpipe from one of the aftermarket vendors?



What type of muffler or resonator did you use (brand name, size, etc. )?



How about hangers, how many, the source, where did you put them, etc.



Did you go over the axle or exit out in front of the back tire?



Any clearance problems to watch out for?



How does the cost for your system compare to those available through the various vendors?



And finally (drum roll please) how do you like it and how does it sound?

 

[dzlcrayz]

It sounds like the best alternative would be for me to put on a 4" resonator for the exhaust. Going to a 5" exhaust is not an option for me right now. I have an IMCO exhaust system on the truck right now with a flow through muffler located in the same place as the factory was. I greatly appreciate everyones help so far.

 

[24V-DSL]

System that doesn't drone....

No help for those with the drone, but for TDR members researching a 4" system, JRE does not drone.



www.jannettyracing.com



I've never seen anyone post that they have a drone with JRE.



No affiliation... . just a happy customer.

 

[Murietaman]

Yipes, the dreaded drone,:{ I also noticed it at all speeds, dead stop to full speed. Come to find out it was "the wife" trying to talk while I was listening to Doo Wop. . I just nodded now and then and said yes dear ocasionally and the drone went away. :-laf :-laf :-laf

 

[Jim Fulmer]

BigMo I bought (2) 30 degree bends and the flang for the HT3B to build the down pipe(painful) as it's all fabricated then I bought a 10' stick of Donaldson 5" pipe that is . 060 thick, ordered a resonator a short 30 degree bend a 90 degree and a 70 degree to put it over the axle and a turn down for the tail pipe, it was no bolt together deal as I had to shortedn the 90 and 70 for the axle pipe. I don't have any good pics of the build as they don't come out good laying on your back, the resonator is 10x16" straight through design. Tight spots are the transmission, resonator to the frame, over the axle and still miss the 245 tire in the rack but it's doable with a chop saw and welder(tig in my case). For the hangers I bought 5" clamps like the 4" ones use and chopped the rods off and shortened them. A normal turbo would work better as the big turbo is closer to the firewall. All of the parts were bought from truck supply and I have $290. 00 in parts into it with quotes from $615-$750 I think I did ok. It sounds great(throaty) but does have a rumble at 14-1500 but nice after that(G-friend says it sounds like a train). The way I learned all of this was laying the pieces fitted together at the truck shop, then had to look at what I would have to modify.



Jim



Jim[/IMG]#ad

 

[BigMo]

Thanks Jim.



That pretty much answers my questions! It sounds like it was worth the effort . . . . you've got a lot of sweat equity in that 5 inch exhaust, for sure.



Now, I'm more tempted than ever! And, with a five inch exhaust, absolutely, positively no worries about EGTs, at least from a restriction standpoint.

 

[JJW_ND]

Have muffler as far forward as possible!

A few of us have had luck moving what ever your using for a muffler as far forward as possible.



When changing to a 4" or 5" your best bet is to use band clamps. Makes adjustments, additions or changes a breeze.



I have seen some installs that had the muffler position between the two 3' chucks that come with most 4" systems rather then having the muffler in the factory location or right infront of the tail pipe.



I tried angle iron and a resonator to no avail. I did put the resonator right in front of the muffler. Better but still noisy at 2K rpms. I then added a second muffler right behind the transmission hanger. Drone gone!



If you have band clamps changes are pretty easy.



jjw

ND

 

[dzlcrayz]

JJW-ND,

What type of muffler did you use? I am not sure if I should use a muffler or a resonator, but by your reply I am thinking maybe the muffler is the way to go.

 

[JJW_ND]

I would move your existing muffler (you used band clamps right!) as far forward first to see if this works. If not, you could try a resonator (just a small muffler). Most are 4"ID both ends so you should be able to cut the first 3' length of pipe (one just after the down pipe ) ... cut 6" or so AFTER the transmission hanger. Double check for clearence if not move back as neccessay. Remove only as much of that 4' pipe neccessary to fit the resonator/muffler inplace. Everything behind should be just fine.



Use band clamps from here on as it will really help if you need to make any more changes.



I did not have luck with a resonator but then I just mounted it directly in front of the muffler, which was in the factory location.



jjw

ND

 

[Devildog]

Has anyone tried the Donaldson M085171 muffler, It has two chambers from what I understand and suppose to stop the drone.

 

[raiste]

I band clamped a piece of angle iron to the long stretch of exhaust pipe and most of my drone went away. Simple and cheap.

 

[Big White Beast]

JJW-ND had it right.........

Just move the muffler as far forward as you can. Most systems have a two piece straight pipe. Just remove one and put the muff in it's place and vice versa. Worked on both our trucks.



I did have the 4" resonator on the 01 for a while but didn't like the sound although it killed the drone nicely. When I went with the allied muffler I moved it forward and haven't had the drone at all.



Garrett

 

[Shooter]

Why Put on 2 or 3 mufflers/ resonators when the Donaldson M085171 works, is about $50 and goes in the original position,

It is straight flow through design, has a center sound trap/ expansion chamber that is the full 8" dia and open with both ends having 4" perforated pipe. It has been used by many TDR members in this area and has not failed to resolve the drone in any of them.

Originally posted by Devildog

Has anyone tried the Donaldson M085171 muffler, It has two chambers from what I understand and suppose to stop the drone.

 

[Okie-Go]

I am thinking about taking my muffler off and putting in a 4' straight pipe. I have the 4' system now. I am kind of afraid of the drone as now I have none. I did have a muffler eliminator kit with the small resonator left on before I went with the 4". I think that is a real neat sound especially when the engine starts to work a little. I want that sound again. Would I need a resonator or should should I just try it and see?