Originally Posted By: m37charlie
Originally Posted By: dnewton3
5) The TBN really isn't an issue any more, because the low sulphur content in fuel and oil and additives means there is precious little acids being produced. I have yet to see a used oil analysis show a TBN issue when ULSD fuel is used for "normal" OCI durations.
What about my BMW X5 35d OCIs, done at 10k mi as prescribed by IDrive, used dealer Castrol SLX Professional OE 5W30? Analysis by Detroit Diesel TWICE got big alarms for TBN 1.5 and high Fe/AL #s(93/84 for Fe; 33/27 for Al); the one time they did TAN it was 4.83.
I can only theorize that because it is likely a "high EGR" engine, the oil got overloaded with nitric acid from NOx production.
Which is why I am now using Delvac 1 LE 5W30, with TBN 12.6 instead of 6.4. I will change and analyze at 13-14K miles just to really stress it a bit.
Charlie
Your observations are valid for your situation; I'm not in a position to disagree with you on your own operations. From what I've read, you're very diligent about your maintenance program.
But your BMW and MB experience has nothing to do with a 2002 LB7 Dmax. There is no EGR on that engine, as best I understand. Of all the Dmax used oil analysis I've seen (and I've seen a LOT of them) I've never seen TBN be an issue in a "normal" OEM duration OCI with ULSD when using a traditional HDEO.
The OP asked if he should try Sinclair. For $8/gallon, I sure would. If he fears the TBN issue, then he can get a used oil analysis to see how it's holding up. Remember, he's only intending to do 6k mile OCIs of "normal driving" with no heavy work. He's probably going to underutilize the oil, but for that price, he can afford to.
Heck for $8/gallon, I'd be willing to be the guinea pig!