I OWN A 2005 GMC 2500 HD WITH LLY MOTOR AND CATALYTIC CONVERTOR. INSTALLED BANKS MONSTER EXHAUST OFF OF 03' LB7, IT FITS GREAT, BUT SOUNDS LIKE A BROKEN AIR HOSE ON A COMPRESSOR DUE TO EXHAUST RESTRICTOR.


DOES ANYONE HAVE A REMEDY FOR THIS PROBLEM? OR DO I HAVE TO PUT THE CATALYTIC CONVERTOR BACK ON?

What do you mean by exhaust restrictor?????

I have same issue I'm going to try a motoblue tip with the built in resonator to see if that solves the problem. It should arrive early next week I will let you know how it works out.

You are hearing the "leaf blower" at idle due to the turbo vanes being commanded fully closed to provide the backpressure needed for EGR operation.

is there anyway to unhook egr valve or to fool its operation to get rid of leafblower noise my lb7 motor must not have been an egr motor

No. My EGR is unplugged, and it still makes the noise. . . you
will even hear it cycle from blowing leaves to sounding good and back.
. . just let it go, man.http://www.dieselplace.com/forum/smileys/hihi.gif

I just installed the full motoblue exhaust and before I had the resonator tip welded on it DID make this loud whining/sucking noise like what you are describing. Just letting you know that the tip DOES baffle this noise.