Originally Posted By: 4WD
Originally Posted By: john_pifer
Originally Posted By: Linctex
Originally Posted By: john_pifer
What do you guys think? Experiment, or stick with what has worked?
IMHO (YMMV) ..... with almost 200,000 miles,
I'd run a 5W-40 or 15W-40 HDEO from this point forward.
It's at 201K now. Last oil change was at 198K.
I'd be resistant to going to a 40W. If I went up in viscosity I might try a 10W-30. At most, M1 0W-40, which, I understand, is pretty thin for a 40.
But, these days, I do like the idea of low NOACK % and fewer VM. So, a 10W-30 is attractive. Again, also, I'm now idling for 60-90 min. per week, and I drive pretty fast on my commute. So, maybe a 10W-30 with a bit higher HTHS than the current M1 EP 5W-30.
Another thought is watch for Delvac 1 5w40 to come on sale … it has similar HTHS to 0w40 but 5w40 is a spread I like … blend of GIII/GIV … stellar in the Blackstone summation … once in a while Walmart.com runs it for $23
Or…
https://www.exxonmobil.com/Xomfl/Core/Handlers/PDFHandler.ashx?component=PDS&downloadUrl=https://www.mobil.com/English-US/Commercial-Vehicle-Lube/pds/GLXXMobil-Delvac-1-LE-5W30?p=1
My only concerns with going the HDEO route would be, 1, the extra ZDDP possibly fouling the catalytic converters, and, 2, this truck has VVT-i. And I've never had a CEL pop...ever.