Originally Posted By: ChrisD46
If two leading synthetic oils generally have good or equal quality add packs , viscosity , etc. would you then look at the oil with the lower NOAK number (as a measure of better quality) to determine which one you would buy ?
The most stringent mfg specs in existence today call for NOACK of 10% or less, so that's probably good enough for even the most demanding applications. Once you get below that level, I'm not sure there is going to be a whole lot of distinction/benefit there.