Originally Posted by OVERKILL
Originally Posted by k9jadon
Why is the 15W40 Valvoline premium blue listed at 12% and other 15w40s are in the 4% range? I am just curious since I do not know what causes an oil's NOACK to be higher or lower. Thanks
Originally Posted by k9jadon
AMSOIL's 15w40 diesel and marine oil is 4.8. And their latest 15w40 Ck4 is listed at 5.1.
https://www.amsoil.com/lit/databulletins/g473.pdf;
https://www.amsoil.com/lit/databulletins/g3467.pdf
The reason I didn't mention AMSOIL in the first place is because I just wanted thoughts on NOACK numbers and not opinions about how great or awful AMSOIL is.
I think one needs to consider that when making ambiguous references to "other" 15w-40's, that when those products are in fact expensive boutique lubricants blended by a company where those are its primary business, that this is not an overly appropriate barometer for the market in general. While I understand the reluctance to spell out the products by name, some indication that we aren't dealing with "typical" lubes of this grade would have been extremely helpful.
Your Joe Average 15w-40, which is the predominant bulk fill for OTR diesels and similar is typically the lowest cost offering by major oil companies because these are high volume sales. The premium offerings are 5w-40 and 0w-40, both of which will use higher quality base stocks necessary to meet their respective Winter ratings. A 15w-40 can be blended extremely cheaply because you can use inexpensive bases from the lower groups to formulate due to the 15w Winter rating not being a difficult bar to meet. This is why major 15w-40's are almost all conventional lubes, with the odd semi.
Mobil's Delvac product line does not include a synthetic or even semi-synthetic 15w-40. Shell produces a semi-synthetic 15w-40, no full synthetic offering. Valvoline does not produce a synthetic or synthetic-blend 15w-40. Anybody ponying up for a synthetic would typically be more inclined toward a superior Winter rating as part of that cost.
So what is "typical" for a 15w-40 will be what the majors have going on for Noack, so I would posit that the 12% for VPB is thus likely "typical". Niche boutique offerings subsequently are a whole other discussion.
Mobil Delvac Extreme is a synthetic blend 15W40, not sure of the NOACK rating. 12% seems to be a fair average for 15W40 oils, not sure what detriment a high NOACK would be in a non-GDI diesel, other than needing top-offs and maybe slight thickening?