Explain M1 0W20 AFE Content ?

[ChrisD46]

In reviewing the PQIAmerica reviews of M1 0W20 AFE (sampled in Feb 2014) it appears the Mobil approach is to use much more magnesium in their recipe than SOPUS does (QSUD 0W20) where by the calcium content in QSUD 0W20 is more than double compared to Mobil . My concern is the the high magnesium content of M1 0W20 which appears better suited for a deisel engine than a gasoline engine ...Your thoughts ? Any reason (based on specs. of M1 0W20 AFE) to run a lower OCI (<7500 miles) on M1 0W20 AFE vs. QSUD 0W20 ?

 

[sicko]

I don't see any reason to run a shorter OCI because of the magnesium. They have similar Calcium and Magnesium numbers in their regular 5w30 ( http://www.pqiamerica.com/March2013PCMO/mobil1.htm ) and again in their M1 EP ( https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2260688 ), and nobody says to run shorter OCIs for them. The EP is said to be good for 15k miles.

 

[ChrisD46]

Perhaps I should word a different way : What are your thoughts as to the high magnesium content of M1 0W20 AFE as compared to other oils that rely on a high calcium content ? ...Hard to say exactly what goes into a add pack but the only other thing I notice about the M1 0W20 AFE is a substantial boron content vs specfically the SOPUS type add pack(s) in a synthetic oil . Do you perceive the M1 0W20 AFE additive package as "less desireable" for a gasoline engine vs. say a PP or QSUD 0W20 synthetic oil ?

 

[SHOZ]

Don't the two basically do the same thing being metallic salts?

 

[Nickdfresh]

I thought I've read here that magnesium was actually (slightly) superior as a detergent than calcium was. But it's more expensive, IIRC...

AFE also has a nice shot of boron...

 

[HKPolice]

AFAIK, only mobil & castrol uses so much Magnesium in their oils and only in the Mobil1 / Castrol Edge lines. None of the dino oils have so much mg. Does it mean that it's better? Only an oil engineer can tell you.

Personally I wouldn't mix an mg heavy oil with a ca oil because their add packs are so different.

 

[gonefishing]

From the PQIA website:

Magnesium is typically related to the detergent additive packages commonly used in engine oils. Detergents are used in lubricants to aid in control of deposits and help keep contaminants suspended in the oil so they can be carried to the filter and removed. In addition, some detergent chemistries also neutralize the acidic by-products of combustion. In doing so, they function as corrosion inhibitors.

In addition to the use of calcium sulfonates, magnesium sulfonates are used in engine oils as detergent additives. Although magnesium sulfonate is more expensive than calcium sulfonate, some formulators reportedly prefer its use due to what they feel is improved rust production seen with magnesium sulfonates as compared to calcium sulfonate in diesel engines. Because of this, whereas magnesium can be seen in the spectrographic analysis of diesel engine oils, today it is fairly uncommon to see it at any meaningful level in passenger car engine oil.