Ok yesterday all the sudden when my pac brake engaged i get this horrific sound from under the hood.. OMG.. somthing is dieing under there.. so pop the hood and it sounds like my top turbo is dieing...only does it with the brake set... i hammered it today and still gettin 58 lbs of boost so not forsure what this is but it doesent sound good.. i took a vid of it and put in on youtube hopefully the link will come in here..thanks any ideas??

Capn

http://www.youtube.com/watch?v=cbZE9tvAGMs

 

Sounds normal to me. Kind of hard to hear though. The brake sounds like any other when it's engaged at idle to me as well. Maybe someone else can chime in and give more information but I'm just not hearing anything unusual.

 

yea the brake is normal..but about a min into the vid this awfull sound starts..had the brake for a year and the twins since march and never heard that noise before..and when i'm driving and it sets...holy crap.. its really bad!! this isnt normal i dont think??

 

Whoa. should have listened to the whole thing. I didn't get that far. yeah, I hear it, and that doesn't sound normal to me.. I'm going to let someone else make the recommendations on what to do though..

 

Well Pac Brake is one of the best for customer relations, I am sure they would help on this.
Having said that could it be a leak.

 

I do have a leak..but it "whistles" when the brake is set..not this ....ummm.. almost like a grinding sound?? I'll be calling pacbrake and BD today...thanks for any info...
Capn

 

Sounds like a wheel rubbing to me.
You might try taking the air inlet pipe off the top turbo, pull the turbo shaft towards the front of the truck and turn it to see if it's dragging a wheel on the compressor housing. If it's still quiet & smooth, push it towards the rear to see if it's an exhaust wheel/housing rub.

You might try the same on the bottom turbo too.

 

A trick an instructor taught me to locate sounds was to take a solid rod or bar, even a broom handle, and hold it to the part you're trying to listen to. Then take the other end and hold it on your ear (specifically the Tragus.... the fleshy part on the OUTSIDE of your ear, when you push down on the little flap it will close your earhole http://en.wikipedia.org/wiki/Tragus_%28ear%29). It'll certainly narrow down what you're looking for.

 

Ummm pull your pipes now!!!!! and see if your Wheel has dropped . Is it only doing that when the brake is engaged ?

 

Doesn't quite sound the same, but you might check the exhaust manifold bolts too. Mine was making a similar noise, turned out one of the manifold nuts was loose.

 

Yes it only does it when the brake sets, and not all the time? I'm still gettin full boost when i'm gettin on it..am i checkin the turbine wheel? Thanks for the info. i've got some time off this week so i'll be pulling the pipes then.

Capn

 

Talked to BD and pacbrake today, got different ideas, so guess i need to wait till it warms up a bit, but first thing will be to pull the pipes and look at the wheels, i also have a gasket comin from BD for the wastegate plate on the top turbo which does leak, so i'll get that on but i dont think its a leak! Thanks for all the ideas..i'll be lookin at everything..
Capn

 

I'll be watching this thread. Please report back. I have a usgear d-celerator in line and the stock turbo, but after building up some pressure (I think) on a long downhill I started to hear that same sound.