Ash content in different base oils.

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Figured the knowledge base on the board could provide some general answers. In a diesel that has a particulate filter and does regeneration, which base oils produce the most ash and of these ashes, which will continue to burn off during regeneration. I may be falsely assuming that I and II may produce more ash but would also be more fully consumed in regeneration and that some III, IV and V may not burn at all. I guess the additive package should also be weighed. Calcium, detergents, Zinc, phosphor's, moly etc. Which base + additive package would offer the most robust protection in the 5W-30 range with a 10,000 mile OCI, but also create little ash that won't be consumed. In my case a direct injected, turbocharged diesel with a 5W-30 spec. I imagine this info could also apply to many other diesels. Edemucate me please.
 
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I have a 2013 Passat diesel (see signature). I know they are really picky about inorganic ash buildup over time and therefore require a VW 507 oil which has a very low inorganic ash content. Oil, which is really just long polymeric molecules of carbon, hydrogen and some oxygen, nitrofgen and a dash of sulfur, should not produce much non-combustible ash on it's own. It is really the additives such as calcium, zinc, etc that you pointed out that form the non-burning as that will eventually load up your DPF over time. I depend on VW 507 specification for oil and always use the Castrol 5W-30. I think the manufacturer's specs will be what you need to follow and not worry what base oil, etc was used to achieve this.
 
I have two EA288 VW's that require the 507.00 spec. I am not real happy with the factory fill Castrol's published performance specs. I want a really low cold pour point but don't want to load up my DPF if it can be helped. Just curious as to how class III,IV and V respond to regeneration.
 
depending on your wallet, a real synthetic $$$$ or fake synthetic $$ as most are today, a search will show many + Mobil I ESP 5-30 comes up + is readily available, Motul + Total Quartz are also approved. mail order is easy, i buy the rarely seen Redline products on line, + if lucky you can get deals on E-bay as i do. walmart ships to store free with a $35 minimum order as well as their in store stock varies by store.
 
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I'm using the Red Line now. Probably go to M1 esp next time. A little concerned over un-burnable deposits shortening the life of the dpf. I want the best of all worlds I suppose. Extreme performance oil that is DPF,Catalyst and EGR friendly. I don't mind paying the price since I am doing a 10,000 mile OCI and the "boutique" oils are only a couple bucks more than the factory fill per quart.
 
Base oil does not produce any ash. The ash that gets created when a motor oil gets burnt is oxides of metal elements in the additives (eg calcium, magnesium, zinc). These metal oxides form a powdery ash which gets collected in the DPF along with the soot particles that are a product of burning the fuel. During DPF regen the DPF is overheated and the largely carbon-based soot is burnt away, thus clearing the DPF, but the inorganic ash from the motor oil does not burn and so stays in the DPF, accumulating over time until the DPF becomes permanently blocked.

This is why mid- and low-SAPS oils exist, to extend DPF life. Base oil type plays little or no part in this situation other than the mid- and low-SAPS oils tending to meet newer specs and thus have performance requirements that demand the use of some synthetic-type base oil.
 
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