Originally Posted By: SR5
Originally Posted By: Ammofirst
I guess the Mobil 1 10w-30HM is fine but I lose the dexos cert. for warranty. Thanks for the heads up on ACEA C3. If I go with a mid saps option how much should I dial back the OCI? Was considering 10k on full SAPS. Did I read somewhere about these mid saps oils offering less deposits ?
Yes M1 10W-30 HM is a great oil, I would happily use it. But you will never find an oil that is both A3 and Dexos1, as the Dexos1 oil is low HTHS resource conserving ( about 2.9 to 3.2 cP) while the A3 oil is high HTHS (about 3.5 to 3.6 cP). Also 10W30 is not a Dexos grade, the only 30 grade is 5W30 under dexos. I sure wish they did allow 10W30, it's a great shear stable and low volatility oil grade, but not suitable for very cold climates, and I suspect GM want Dexos oils to be suitable for most expected climates.
If you want a high HTHS Dexos oil, then you should get a Dexos2 oil, as this is close to a ACEA C3 oil by another name. It's not just for diesels, but also petrol/gas engines under high stress or race conditions.
Here is a link to the Valvoline SynPower oil data sheet
(Here)
You can see the American ILSAC / Dexos1 oils have a SAPS / SA level of 0.93 %, and for another data point regular M1 5W30 has a SAPS / Sulphated Ash of 0.8 %. This is your regular SAPS level.
Now the Euro A3 oils are true high SAPS oils, with SA of about 1.2 %, for Euro long-life ratings, often used for 20k miles or 2 years in Europe. But the mid-SAPS C3 oils have a SA of 0.78 %, basically 0.8% or a touch under. But this is the same as regular M1 5W30.
In my opinion, anybody using a ILSAC GF-5 or Dexos1 oil, is already using a mid-SAPS oil due to the limits imposed by ILSAC and Dexos. Going to a C3 oil shouldn't make much difference. If you use a Dexos2 C3 oil, you should be able to follow your GM OLM. If you are still concerned change at 20% or 7500 miles.
Thanks very informative. Does Pennzoil consider this a low saps oil.
http://mxtradings.com/Pennzoil/PU5w30EuroL.pdf