There's been a few threads on this, including ope126's excellent thread on Ecoboost oils. But the whole issue of the M2C913-x oil that Ford specify for our engines can not only be confusing for the owners, but also some Australian oil suppliers going by the oils that they recommend through the oil selectors on their websites.
Most of the following is based on the oilspecifications.com website, and also information provided by Lubrizol regarding ACEA oil specs. I've tried to keep it brief, but have failed badly! I've had to join the dots to some extent, so please let me know if I've got anything wrong.
M2C913-x (D is current) is Ford's oil specification for most of their European petrol and diesel engines. M2C913-A was published in the late 1990's, and has been updated about every 5 years. M2C913-C is specified for most MA - MC Mondeos, but was superseded by D during 2013. The upgraded specs are
generally backwards compatible with the older, so if your handbook specifies M2C913-B or C, then you should use the latest M2C913-D oil.
So far, so good, and if you own a petrol Mondeo, there isn't really an issue other than finding a product in consumer packaging that meets the spec. The Ford factory fill and recommended oil is Castrol Magnatec Professional A5, but the smallest container is 20 l. There's much more info in the post by ope126 on Ecoboost oils. Be aware that just because the oil container states that it meets M2C913-D doesn't mean that it's actually been
tested against the Ford spec, especially in the case of Australian oils. The oil company may have just bought an additive package from Lubrizol that is designed to produce a M2C913-D oil, so it might pay to check with the manufacturer whether it has been tested.
A little background here. ACEA oil specifications are developed in Europe by a group representing European carmakers. Usually, there will be an ACEA spec that aligns with a particular manufacturer’s OEM spec, e.g. C3 with Merc, VW, etc. The ACEA A/B oils are generally for gasoline and light diesel engines without DPFs. The C series also includes specifications to ensure that emission controls, particularly the DPF, aren't damaged by certain additives such as phosphorous. This is where the “low SAPS” marking that you will see on some oils comes from. (SAPS = sulphated ash, phosphorous and sulphur)
I don’t have a copy of M2C913-D, and I’m unsure how much it would all mean to me anyway. But it aligns with A5/B5-10, so it appears that it doesn’t include a SAPS limit. If it did, then you’d expect that it would align with one of the ACEA C specs. This is confirmed by the manufacturers’ specs, for example Castrol Magnatec A5 has 1.24% sulphated ash, which is much higher than the C2 and C3 limit of 0.8%.
Now this is where it becomes interesting. ACEA A5/B5 is a fuel economy oil, as are the C2 and C3 oils. However, in order to enable the oil manufacturers to meet the C specs, ACEA has relaxed some of the additive requirements. For example, A5/B5 oils must have a TBN greater then 8.0, whereas C3 specifies 6.0 and C2 doesn’t include a minimum. (TBN = Total Base Number, which is a measure of the total amount of certain anti-wear additives.) However, the maximum wear requirements are almost the same between A5/B5, and C2 and C3.
One final thing to note about M2C913-D is that it is required for a small subset of Ford diesel engines, specifically the 2.2 l engines fitted to some Transits. Also, the Motul data sheet for their 913-D oil states:
The “913 D” specification requires also an extra high oil film resistance for the lubricant to guarantee the viscosity capability over the whole oil drain interval. This characteristic is even more important in the current sustainability context and use of bio fuels such as biodiesel.
Make of this what you will. It may be that the Ford spec oil is intended to provide an additional degree of engine protection over C2 / C3 oils by not including a SAPS limit. This is why some oils that are recommended for Ford diesel engines also state that they should not be used where DPF’s are fitted! However, Ford specify the same oil for most of their Euro products, so maybe they just wanted to have a single oil that could be used in almost all of their engines, and feel that the DPF won’t be too affected by the higher SAPS levels.
Peugeot recommend C2 oils for their version of the Mondeo diesel engine, but also have an OEM spec that is met only by a Total oil. (I wouldn’t like to speculate why this is, except to say that both are French companies!) But having looked at the ACEA oil specs, I may just buy the best value C3 oil that I can find when Repco or Supercheap next have a 25% off sale.