How many miles would you expect to get before replacing a turbo. What would be a sign of impending failure? Looking at a quatro with 153k miles, well maintained.
turbo replacement on 2000 Audi TT Quattro
That is really depends on the maintenance, the quality of oil that had been used, driving conditions, etc.. but at 153K you got a good life out of the turbo. Many of the 1.8T engine won't last much over 100K. Google 1.8T engine problems and you will see what I'm taking about.