Hello, I recently found a problem with what appears to be the turbo for my 2008 Freightliner Colombia Detroit- S60. Every time I start up the engine, a loud whistle noise can be heard. If one then steps on the gas pedal the noise increases far more than the usual turbo noise. I tried testing for any abrasions or holes on the hoses connected to the turbo by spraying some water and hoping to see bubbles form but I really couldn't find the issue there. I was hoping to get some help on how I should open up the turbo and what I should be looking for once I open it up. Any bearings or shafts, etc.
(I posted this image just to show a turbo but its not my trucks)
(also if you happen to know a good place to buy some turbos for a fair price please dm me or respond)