buickanddeere
Super Member
That CJ-4 blend may or may not provide less protection than CH-4 or CI-4 oil. Unless the CJ-4 oil also has CH-4 or CI-4 on the label. It does not meet the more stringent anti wear specs or the earlier oils.
What weight Oil does a given manufacturer make and why
- Thread starter Silvic
- Start date
That CJ-4 blend may or may not provide less protection than CH-4 or CI-4 oil. Unless the CJ-4 oil also has CH-4 or CI-4 on the label. It does not meet the more stringent anti wear specs or the earlier oils.
Copperhead
Veteran Member
Then why, regardless of brand, does the CJ-4 spec that meets the API standard always say it is backward compatible? Is there some dirty little secret regarding CJ-4 that you know that the American Petroleum Institute is withholding from us? Millions of commercial trucks that have engines that were built with CH-4, CI-4, and CI-4+ in mind have been using CJ-4 for years and racked up over a million miles per engine with no major repairs or oil related issues. Direct from the API website itself.....
API CJ-4 oils exceed the performance criteria of API CI-4 with CI-4 PLUS, CI-4, CH-4, CG-4 and CF-4 and can effectively lubricate engines calling for those API Service Categories.
http://www.apicj-4.org/2009_ENGINE_OIL_GUIDE.pdf
My last two semi trucks and my current one, the motors were all made when CI-4 was the standard. They all got CJ-4 when CJ-4 first showed up. Nary a problem. The current motor is a Detroit Series 60 12.7 pre-egr that is a factory reman crate motor. It has only gotten CJ-4 since it was installed. 476,000 miles on it and it is one of the best motors I have ever owned.
API CJ-4 oils exceed the performance criteria of API CI-4 with CI-4 PLUS, CI-4, CH-4, CG-4 and CF-4 and can effectively lubricate engines calling for those API Service Categories.
http://www.apicj-4.org/2009_ENGINE_OIL_GUIDE.pdf
My last two semi trucks and my current one, the motors were all made when CI-4 was the standard. They all got CJ-4 when CJ-4 first showed up. Nary a problem. The current motor is a Detroit Series 60 12.7 pre-egr that is a factory reman crate motor. It has only gotten CJ-4 since it was installed. 476,000 miles on it and it is one of the best motors I have ever owned.
buickanddeere
Super Member
If the low ash CJ-4 oil does not say CH-4 or CI-4 . Then it does not meet the anti wear specs of the CH-4 and CI-4 oil with more and different anti wear and anti corrosion additives .
Not every brand and version of SJ-4 is backwards compatable .
Not every brand and version of SJ-4 is backwards compatable .
Copperhead
Veteran Member
True, ZDDP levels were reduced, but there is a corresponding increase in boron, moly, and in some cases, titanium, which all have properties that negate the higher levels of ZDDP in the past. And there is no appreciable evidence of a statistical nature that remotely suggests that CJ-4 HDEO's are not sufficient to provide more than adequate protection. Else, there would be a significant rise in motor component failures and you would see myriad of commercial trucks broke down everywhere. Still the majority of commercial trucks on the roads have motors that are pre CJ-4.
Per the API specification.. if it meets CJ-4, then it meets all the previous specs and is backward compatible. That is a requirement of a HDEO that meets CJ-4. If it cannot protect as well as a previous spec, then it does not meet the CJ-4 spec. All CJ-4's have low ash rating of 1.0 or less. That is a requirement of CJ-4 to meet emissions component protection. Ash in oil is from the metallic additives of ZDDP. Other metals are able to more than protect cams, bearings, etc. Moly and titanium the premier ones.
Per the API specification.. if it meets CJ-4, then it meets all the previous specs and is backward compatible. That is a requirement of a HDEO that meets CJ-4. If it cannot protect as well as a previous spec, then it does not meet the CJ-4 spec. All CJ-4's have low ash rating of 1.0 or less. That is a requirement of CJ-4 to meet emissions component protection. Ash in oil is from the metallic additives of ZDDP. Other metals are able to more than protect cams, bearings, etc. Moly and titanium the premier ones.
prs
Platinum Member
Copperhead, in post 18 above you mentioned "S"class oils, "SN" as I recall. My recollection agrees with you regarding "C" class oils being retro-inclusive. However, my foggy memory seems to strore a memory where "SN" may not be inclusive of specification requirements of previous "S" class lubes. It may have something to do with pollution standards or additive packages that are not desirable in some new spark engines.
Rooster
Rooster
buickanddeere
Super Member
Just to be sure . We should double check with a couple of oil company reps if all oils are all back compatable as in the old "pre emission " days.
On a related topic. Many a two stroke Detroit has been ruined when somebody thought "newer/better" spec oil. When the additive package scored the rings and plugged the ports.
On a related topic. Many a two stroke Detroit has been ruined when somebody thought "newer/better" spec oil. When the additive package scored the rings and plugged the ports.
Copperhead
Veteran Member
SN is an improvement on SM and SM is backward compatible with SJ, SL, and earlier categories. All per API. SN has superior sludge and piston deposit protection over SM, yet has the same wear and oxidative thickening of SM, along with better turbocharger and emission systems protection, along with features specific to using E85 fuel. SN was developed as basically an SM oil that also meets the specifications of ILSAC GF-5. API SN is backward compatible as is ILSAC GF-5.
API Motor Oil Service Classifications
The new SN and GF-5 rated motor oils are backwards compatible and may be used in 2010 and older engines.
It further states that there is a reduction in ZDDP anti wear elements in SN, as I stated earlier, but motor oils now contain higher levels of moly or titanium and boron as substitutes for ZDDP. For instance, the Schaeffer 5w30 SN rated oil I use has 309 ppm of moly (highest of all the major brands), along with 71 ppm of antimony, and boron. A very stout combination that provides more than adequate protection of ZDDP. So, while ZDDP (Zinc / Phosphorus) is the more commonly known "old school" way of providing anti-wear protection, moly or titanium, combined with higher levels of boron is the new way of doing things. Given the qualities of moly and titanium, I believe it is a more preferred and superior alternative to ZDDP. Moly (MoS2 or molybdenum disulfide) will withstand over 2000F and pressures of 1/2 million PSI, while only having a layer of 1 micron.
Three articles on the stuff.....
Moly Basics - Bob is the Oil Guy - Bob is the Oil Guy
API Motor Oil Service Classifications
The new SN and GF-5 rated motor oils are backwards compatible and may be used in 2010 and older engines.
It further states that there is a reduction in ZDDP anti wear elements in SN, as I stated earlier, but motor oils now contain higher levels of moly or titanium and boron as substitutes for ZDDP. For instance, the Schaeffer 5w30 SN rated oil I use has 309 ppm of moly (highest of all the major brands), along with 71 ppm of antimony, and boron. A very stout combination that provides more than adequate protection of ZDDP. So, while ZDDP (Zinc / Phosphorus) is the more commonly known "old school" way of providing anti-wear protection, moly or titanium, combined with higher levels of boron is the new way of doing things. Given the qualities of moly and titanium, I believe it is a more preferred and superior alternative to ZDDP. Moly (MoS2 or molybdenum disulfide) will withstand over 2000F and pressures of 1/2 million PSI, while only having a layer of 1 micron.
Three articles on the stuff.....
Moly Basics - Bob is the Oil Guy - Bob is the Oil Guy
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Copperhead
Veteran Member
But the 2 stroke Detroits called for straight weight oils, not the multi vis that is common now. No straight weight will meet the new specs anyway. If someone screwed up and put a newer spec multi vis oil in a Detroit 2 stroke, that is not anyone's fault but theirs. The add pack of a straight weight is different than that of a multi vis oil. Put the blame where it lies, on the idiot who put in the wrong oil. One has to use a CF-II straight weight in it (the last spec designed for the 2 strokes), and good luck finding a CF-II rated straight weight on a shelf. But it isn't like there are myriads of 2 stroke Detroits running around the countryside, and to even use it in a discussion that centers around 4 stroke diesel and gas engines is extreme. There are always exceptions to anything, but whether they are pertinent to the discussion is another. I wouldn't use a modern SM or SN oil in a Ford Model A either.
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