Turbine Shaft Bearing: Design & Application

Hello!
I have a question regarding the storage of Garrett VTG turbochargers... Do they have axial bearings in addition to the radial bearings, or are the axial forces low enough that axial bearings can be omitted?
"I'm experiencing a problem where the turbocharger whistles very loudly at low RPMs (around 1100-1400 RPM). You can clearly hear the loud noise "normalize" when you exceed a certain turbocharger speed. What could be causing this? My suspicion is that it's resonance vibrations that are causing the noise and also preventing the turbocharger from spinning up (at idle, when slowly pressing the accelerator). As far as I know, plain bearings shouldn't wear out if they are properly lubricated? Could it be that the oil pressure is too low at low RPMs to form a proper lubricating film?"



Sure, here is the translation of the text from German to English:

"Hi, thefirefly"