WHISTLE TYPE NOISE ON AN 871 ENGINE

[RTRUCKING48]

Hello fellows, i just got this 09 prostar in december 2015 so I'm kind of new with this isx 871 cummins 670K mileage, I'm getting this noise on the driver side kinda like a whistle some times like the turbo noise specially when claiming a hill and It also smokes white blueish smoke while doing this, and when I finish claiming the hill and if I try to engage my engine brake the engine brake makes like a rattle noise by the turbo not loud but I can tell its not normal my shop check the VGT and the turbo they did the recalibration and everything was good I also change the air to air charger because it was leaking and all of the hoses and clamps, lately I notice I been loosing little bit of power and its doing it more i already performed the Egr Tune up 2 months ago and took the Egr valve off to clean it was not the original red color now its all green it seems that it was replaced already it started doing all this like 2 weeks ago so I need a little help here maybe some of you have the same issues before similar to mine and I would like to know what it's wrong with it,you guys think it may be the Egr valve it's going bad not opening or closing?? I'm in the process of getting my insite, so far I haven't have any engine warning lights or codes, thanks in advance..