stock exhaust drone

[jason372923]

Hello everyone, I have a Laramie etorque hemi with just over 1,000 miles. The stock exhaust sounded great but seemingly out of the blue it now has a weird drone at certain rpms. I don't even know if drone is the correct word it almost sounds like bass but it's definitely coming from the exhaust. I thought maybe my tonneau cover but with it rolled up i still get it. I also added the rear wheel house liners but the sound was before those got installed.

Any ideas? Thanks

 

[Bdog]

I bet it is when you go into 4cyl eco mode. You can set it in the options to show “eco” by your speedometer when this happens. Mine makes the same sound when eco engages. The only way to turn off eco is to manually select gears.

 

[jason372923]

Thanks for the input! I have the eco light set to on and do notice it happens more when it's on. Just strange to me how it changed from the first 500 miles i put on the truck.

 

[768mph]

Thanks for the input! I have the eco light set to on and do notice it happens more when it's on. Just strange to me how it changed from the first 500 miles i put on the truck.

Could be the sound cancelation system (amp under drivers seat) they have been malfunctioning. Especially if this showed up out of the blue.

 

[jason372923]

Thanks! your advice got me thinking and I did put new 6x9 speakers in the rear doors at about that time. I just put the stock ones back in and that completely fixed the problem so yes it must have been the noise cancellation doing something funky with the new speakers.

 

[Goatmann]

Thanks! your advice got me thinking and I did put new 6x9 speakers in the rear doors at about that time. I just put the stock ones back in and that completely fixed the problem so yes it must have been the noise cancellation doing something funky with the new speakers.

what is different with the stock speakers vs the ones you bought for replacement?

 

[jason372923]

I got the JBL Club 9360 for the rear doors that i had seen recommended on another thread. I also have the JBL Clubs for the front dash speakers but those didn't mess with the ANC. Not sure what's different exactly but that was most certainly the culprit.

 

[768mph]

Thanks! your advice got me thinking and I did put new 6x9 speakers in the rear doors at about that time. I just put the stock ones back in and that completely fixed the problem so yes it must have been the noise cancellation doing something funky with the new speakers.

Yes sir. Glad it fixed it.

 

[Nails]

Interesting and glad to hear your fixed up. I’ve actually been hearing my boom from eco and out intermittently. Guess I’ll have to get that checked. Mines all stock and just 10 speaker alpine not Harmon. Didn’t know alpine amps where issues also.