Originally Posted By: Klutch9
Originally Posted By: Char Baby
I never thought that Semi's used a HDEO 10W30. I thought they almost always used a 15W40 or heavier 20W50.
Heavy Duty Engine Oil(HDEO) 10W30 compared to Passenger Car Motor Oil(PCMO) 10W30 oils are different. HDEO's are also labeled as "C"(CE, CF etc.) for commercial use
The HDEO would have additive for better "Soot Control" and probably WILL NOT be "Energy Conserving" compared to a PCMO.
Therefore, the HDEO may also be a bit heavier in it's cST measurement(a heavier weight(ed) oil) but, still a 10W30 by definition & spec range!
IDK if I said that right! Others will chime in with more/better information. But, the HDEO would/could be more protection than needed(if that's even possible!).
Not really significant, but I thought the 'C' in ratings stood for compression, as in compression ignition/diesel engines. Much in the same way the 'G' in the ratings stands for gasoline.
Well, I won't tell you that "C" doesn't stand for compression but, I have never know this to be! This is a quick piece that I found on a site that explains some of the oils lettering.
_________________________________________________________________
In the top part of the donut the words “API Service XXXXX” (5) indicate the type of engine and performance the oil provides. API Service SN the current rating means “S” for Service Station oil (for gasoline engines) and N the current level of service. Or it will say “API Service CJ-4.” API service CJ-4 means “C” for commercial engines (diesel engines) and J-4 where J is the current performance level and 4 indicates a 4-stroke diesel (a 2 will be used for 2-stroke diesel engines).
Here's the link:
http://www.pennzoil.com/learn-about-motor-oil/types-of-oil-and-recommended-use/