I just bought a 2019 QX60 Luxe AWD ~104K. Immediately went to Nissan and got an oil sludge flush/oil change (dealer said minor sludge build up) CVT Drain & Fill Service & AWD gearbox service. What are some issues I should look out for? I've been reading up (sludge, CVT, engine replacements etc) and im concerned. What's some real world issues you have dealt with? Also, what are some positive aspects regarding this QX60. Thanks