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How to stop the dreaded drone.

2258 Views 7 Replies 6 Participants Last post by  409Cummins
I know its really cold right now and nobody wants to be doing anything to their truck if it means being out in the weather but I think I may have found out something interesting. I have the stock exhaust straight piped. Love the sound but hate the drone while towing. I remember reading a long time ago that someone thought about adding metal to the exhaust pipe to reduce or stop the reverberating noise at certain RPM's. Basically saying that the exhaust pipe is like a guitar string. Not sure what the outcome was but I thought for a few bucks, what would it hurt to try? So I got three large hose clamps and a 4'-5' T-post without the spade on the bottom. I laid the T-post on top of the exhaust section where the muffler and resonator was removed and clamped it down with the hose clamps. Now maybe its just my imagination but I think the in cab drone has been reduced significantly. I still haven't hooked up any trailers for that test but so far so good. If this really works then I might just go down and buy some stock to replace the T-post and have it tacked to the exact spot the T-post was.
So if any of you suffer from the same annoying drone, try this! It cost me a whopping $5 and about 5 minutes. Give some feedback if you do try it. Maybe the placement of the T-post (or whatever used) would give different results.
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nice man!! nver thought of that. I might do a couple of those when I put my stack on. It makes sense
I love the drone... helps me remember I have a BAD arse truck!
The drones alout mellower with my straight 5 inch then my old ladys mouth :thud:
Something to keep in mind. My drone drives me up the wall, its a new truck to me and I swear to go it sounds like my damn tires are coming off at 1500- 1800 RPM. I am going to get a full exhaust system and see if it is any better than the splice job my truck came with!!!! If not I will give this a little more serious thought.
good job on the research bubba :thumbsup oh and btw the turbo in your avatar looks a might warm!
good job on the research bubba :thumbsup oh and btw the turbo in your avatar looks a might warm!
You should have seen me trying to take the picture while going down the road.:rof Just kidding.

Actually I even thought about going down to the local semi truck parts shop and buying a 4-5' piece of 4" exhaust pipe and a couple of 3" to 4" reducers and putting it where the muffler/resonator used to be. AS the exhaust gases come to the 3" to 4" expansion they slow down incredibly fast. They also exit the remainder of the exhaust because of the reduced velocity and while this whole process is taking place the sound waves get interrupted and tend to cancel themselves some. If you've ever noticed upon removal of the stock resonator, the exhaust size also goes from 3" to 4" in the resonator and into the muffler at 4" where its reduced back down to 3". I'm sure there was some science behind that too. The only thing thats stopped me is the megal cost of about $50 for parts and probably another $30 or so to have a shop weld it in there, unless I use clamps.
did you ever try pullin the trailer with the clamps?
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