04 Auto making a popping sound?

[BigDaddyMC]

I know that I'm not going to explain the sound characteristic correctly, but here it goes.



Under acceleration and at about 45 - 55mph (little bit of foot into the peddle), when I let off and get back into it or sometimes just taking my foot out and returning it to a nice and easy position, I hear a loud bang or snap/popping sound. It sounds like it's coming from under the vehicle, and sounds trans related. Everything seems to be running fine. I have tried to reproduce the sound and have been able to on occasion.



Any ideas



The trans did it with and without mods - however don't have my profile done yet... .



04 2500 4x4 Quad Cab, long bed with the 48re.

4" exhaust, Tri-pillar with Autometer Ultralites, EZ on setting 4 and a cool air intake with proguard 7 filter.



HELP!

 

[rbattelle]

Maybe you've got a Hemi and it's backfiring?



Seriously, maybe turbo bark?

 

[BigDaddyMC]

Actually... . it does kind of sound like a bark of some kind.



so... ... . I'll bite... What on earth is TURBO BARK?



three turbo diesels before this (Never a cummins) and I've never heard of such a thing.



Help Please

 

[rbattelle]

Well, turbo bark, as I understand it, is basically compressor surge. When you're into the throttle and boost is high and you suddenly release the throttle, there's a moment of time when the manifold pressure is very high and your turbo is no longer making enough power to produce that kind of pressure. The result is that flow reverses, and travels through the compressor backwards.



This is extremely bad for the compressor. It can be avoided by making your throttle foot a little slower.

 

[Ladders]

Yes, it sounds like a "bark" only had it happen once in the VA hills with 30#s of boost and let off too quick (had a slooow moving F mdl move in fornt of me on the hill and I was towing - he/she wasnt ).

Also, never saw more than 1100* before on the hills w/ the 30#s boost. Glad I put the 4" on and the BAHF before the trip.



SOTSU!!

\\BF//

 

[DF5152]

mine does it to mostly during the big RPM jump from 3rd to 4th and alos believe it to be turbo bark