Turbo Failure: Oil Contamination
How contaminated oil damage turbocharger?
The turbo bearings are under great stress when the turbocharger is operating. Since the turbine shaft and bearings rotate in a thin film of oil, any fault with the oil supply to the turbo means the bearings and shaft is likely to fail.
If the oil supply to the turbo is contaminated, the dirty oil will scratch or score the bearing, resulting in turbocharger failure. So it is important to check the engine oil pressure meets the manufacturer's specifications, it is more important that the oil feed lines to turbo are clean and clear.
What causes contaminated oil?
A blocked or damaged oil filter.