Got a Flo Pro 5" tbe and now have a bad drone at 2100 rpm or 75 mph on the highway. It is bad enough that it makes one of the back windows buzz. What can be done about this? 2007.5 dually, throttle valve,egr cooler deletes.

Thanks,
Mike

 

I have the same drone at higher rpm's when towing and the motor starts to lug. The only way I've delt with it is to manually down shift. I have been using tow haul more often and it seems to help the tranny shift earlier. I asked about this drone in a earlier thread and a response from another member was to install a Donaldson muffler. As i remember he said a 51 inch. My local shop said he could install a 31 inch, but didn't know if it would take care of the drone. Also, would a baffled muffler reduce performance? i hope you get some response on this from knowledgeable members.

 

I had the same problem and delt with it for a while. I couldnt take it any longer, so I just put a muffler on it any muffler will do as long as its the right size. mine is off an 08 dodge and it fixes the drone. my cat is also missing btw so i still get the noise just not as loud.

 

I'm not sure I qualify as knowledgable but...... I too have a 5" system. I also have a 51" Donaldson muffler. My drone is definatley present but at 1450 rpm. It is rather obnoxious for anyone else in the vehicle. After about 100k miles I no longer even notice it unless someone points is out. I have searched for cures but have long since given up. I realize this doesn't help too much, other than to say I wouldn't count on the Donaldson to cure that problem.

 

Ensure your hangers are properly hung. Many drone issues are hanger related.

 

here's a old thread that talks about the "drone" and what was done to slove it.

https://www.dieseltruckresource.com/....html?t=248546

Joe

 

sr4440, thanks much for this info.

 

Good reading!! I plan on getting a 5" and I am very glad you posted that thread!!! Thanks again!!

 

A resonator should help with the drone.

 

My 2 cents...I installed Flo Pro 5" turbo back (with their straight thru muffler) on a '08 quad cab and I have no issues with noise/drone!
In fact, I like the noise it makes, a low, deep growl.

 

Thanks guys, I think I'll try the muffler route. The kit that Flo Pro sent me had muffler clamps in it so I subed in some Torctite clamps that make a sealed joint. I wonder if this makes it worse?

 

Are you running an exhaust tip? Getting the exhaust exit further away from the body of the truck can help alot.

 

After relaying the information from this thread to my local muffler shop,,,they built me a 15" resonator and placed it close to the down pipe. I only have about 25 miles on the truck since, but the vibration i had at idle is gone and the sound is quieter. We're heading to Arizona after Christmas, i'll know if the drone is gone then.

 

Yeah, have a 5" to 5" silverline tip on it.

 

I have the same system and used the same clamps and mine drones at 2200 rpm (85mph). I never really cared about it because I usually don't run that fast anymore. I have a 51" donaldson that I had planned to put on as soon as I figured out how I wanted to modify the muffler to remove the baffle and turn that section into an expansion chamber.