I'm curious what the bottling date is on the jug. It probably doesn't matter, but curious because Chevron changed the 15W-40 SDE from 2017 to 2018. In 2017, SDE looked just like this sample (other than the viscosity of course), but in 2018 they added over 100 ppm moly and over 300 ppm of boron. So I can't help but wonder if there have been any changes since your (XLE) sample was blended.
Originally Posted by Gubkin
Originally Posted by SubieRubyRoo
but I was really shocked by the low TBN!
why lab use ASTM D4739 for virgin oil ? It's only for used oil
Yup this lab used ASTM D4739 (as does Blackstone) for a VOA. The oil companies, PQIA and (I would guess) most labs use ASTM D2896 for VOA while reserving D4739 for UOA. Just something to note because it does make the VOA TBN look much less impressive. There's variation in results from lab to lab, too.
I've done some long OCIs with this oil in my Detroit powered OTR truck and I'm most impressed. My longest so far was ~58k miles in which it burned about 7900 gallons of fuel and accumulated ~1600 hours. For that OCI, the TBN was down to 1.9 with TAN at 6.09 and the viscosity was still in prime condition. It's a fabulous oil that doesn't come at an exorbitant price. I'm still using XLE but I think I'm going to try SDE again next.
Thanks for all of your recent VOAs Subie!