That is weird on Amsoil NOACK. I have been testing oil since the early 1990 and so far the results with Amsoil comes back pretty darn good. My Lexus oil change was great with over 12K miles. I can still keep going on the same oil..The NOACK is what they state since I add about 8 oz of make up in 12K miles….That means a very good NOACK rating here.
Here is what I beleive is happening . You obviously have good ring seal but after seeing 100's of Amsoil Xw-30 wt analysis's at high mile intervals I would imagine your oil was oxidized from heat , your emissions systems on that particular engine and what little engine blowby you might have and had thickened well into the 40wt range . I have seen some approach 50wt range .
When oil is thick , the better the ring seal . With any engine the rings will seal better with a 40wt than a 20 wt and when an oil suffers oxidative thickening at 100c " where the lab tests " it also is much thicker at 40c when engines burn oil also , during the warm-up phase .
Elf , a premier foreign oil company pays particular attention to such oxidative thickening as does the ACEA where all used the older TU3MH bench test that has been superceded to the newer and much more demanding ACEA TU5JP which relates to oxidative thickening at 40c concerning A5 , A3 and 98 oils and how it relates to fuel mileage over the course of an oil change interval .
I don't mean any harm to you or your judgement on analysis but I've been around the block reading analysis for awhile and pretty much 2+2=4 here in your case IMO .
You are using the OAI lab aren't you
I've seen them OK Amsoil for further use when very thick before .
As far as trying the Maxima to compare , you can but one has to trend any oil . Trend analysis is a key couple words there and one trial may not be enough unless the oil a guy is using is simply not close to cutting it in the first place .
As far as the larger amount of zinc in the Maxima and me being sold on it , you do know active zinc is depleted over time don't you ? It also serves as a very good anti-oxident . I'd also not underestimate the function of antinomy in a gear box along with large amounts of sulphur .
Maxima is using cutting edge technology of tommorrow in todays world . It's a race oil that is very street friendly but may not be for everyone . I don't have a vested interest so it does not matter to me what everyone else uses . I help when I want or can but mostly all I care about is what I've learned and put it to use when I buy oils because I really beleive oils are tools and to pick the right tool for the job at hand is better than using a Crescent wrench on everything .
Thats why I use
Synergyn
Fuchs/Silkolene
Maxima
Adios on this topic / thread
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