Originally Posted By: Gokhan
Originally Posted By: Lethal1ty17
I've done a UOA with both M1 EP and Pennzoil Ultra. Though it was a few years ago and the formula has changed, the Pennzoil had much more aluminum wear.
From the viscosity increase, it looks like you may have had an oxidative oil failure with Pennzoil Ultra Platinum (PUP) with the long OCI you tried.
I would say next time try a dexos1 Gen 2 0W-20 instead of a 5W-20, as it tends to have a better base oil, which is more suitable for extended OCI's. The mostly GTL Super Tech High-Mileage 0W-20 is a great choice. Mobil 1 AFE, EP, and AP 0W-20 have even better base oils, a little higher TBN, except with the caveat of possibly somewhat higher iron number (valvetrain wear) because of some ester in base oil. If you don't have GDI, Genuine Nissan Motor Oil 0W-20 is also a great choice, with the best GTL formulation out there but no moly and Mg, available cheaply on eBay.
I have asked before why is PP not marketed for long OCI like Amsoil, Castrol, Mobil 1 etc …