I recently have had a really loud droaning that seems to be from the muffler at 1500-1800 RPM and it's making me crazy. I had my driveshaft rebuilt so I know it's not coming from there. Has anyone else had this noise from their muffler? It seems to get worse every time I drive since I did the downpipe and delete pipe.

Also, has anyone towed a 14K trailer with my setup? I have a 3.73 diff.

 

Wish I could help you, but my muffler ended up in the dumpster a long time ago. I'd just take a sawzall to it. That will fix the sound

-Robb

 

I thought about that. With the delete pipe, the muffler seems like it's just a resonating box. When it hit a certain frequency, it just starts to sing. I really don't want it to be any louder than it is now, though. I have a hard enough time convincing my wife to take the truck instead of the minivan right now. Louder wouldn't help.

 

thats about the area to get droan in these mills, not a whole lot you can do for it, mine got better after i put an extension on my tailpipe to bring it out past the side of the truck instead of ending at the truck

 

I thought about wrapping the muffler or something. Is the sound at the opening of the tailpipe? I thought it was the muffler vibrating.

 

are you sure the DP isn't rubbing the firewall?

 

i know mine isnt,(just had it out for heat wrapping) but there is a noticable drone in that rough rpm range. i think mine is highway speeds at around 1700-1900. the exhaust is noticably louder then any other rpm range. lengthening the tail pipe a mere 3-4 inches did wonders for me

 

I'm pretty sure. I have about 1/2" of clearance. I'll check it out, but it sure doesn't sound like it's coming from the firewall. It's also not a sharp sound. It's definitely a low hollow sound.

 

c00nhunterjoe, did you lengthen the tailpipe by adding a tip or bolting or welding?

 

resonates through the whole cab but goes away with just a hair more or less rpm? sounds like wjhat i have. mine may be a little worse running larger pipe with no muffler. i dont know if you have a cat or not but if you gutted your cat and reinstalled it can get worse if you did it that way vs replaceing the cat with striaght pipe

 

I have a delete pipe. I notice it most on the highway also and if I let up just a little or get it past 1800 RPM or so then it goes completely away. It really sounds like a resonant frequency problem. I was thinking either getting rid of the muffler or switching to a different kind of muffler would make it go away. I can't believe no one else doesn't have the same problem.
I bet with some back pressure, that sound would go away.

Gotta leave work now, back online in a couple hours. Hehe.

 

i have exactly what you describe, is your exhaust stock pipe? if so try extending it just a bit to bring the opening out away from the underside of the truck

 

I have the stock pipe and muffler. Would you extend it by welding onto it or adding an exhaust tip? I did a little experimenting on the way home and it seems like I really need to be under a load at higher speeds to get the sound.

 

all i did to mine was put a 5 inch diameter tip on mine that brought the end of the pipe completly out from under the truck. its homemade and crude but it works till i get the materials i need to build stacks

 

I think I'll try it. Now I have to find one.