Thanks for you input, good to hear.
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Regarding my question on Sulphur, I found this
useful article.
The main points:
' Historically sulfur when used in lubricating oil formulation chemistry it has been used as an additive for an antioxidant, part of antiwear (AW) compounding, extreme pressure (EP), and enhanced lubricity properties (the oil's ability to lubricate under boundary metal-to-metal contact conditions).
Emission regulations in engine oils represents the area of most change in limiting the amount of sulfur allowed in today’s lubricants. Reduction in fuels and engine oil has impacted lubricating properties required for fuel injectors and other engine components by reducing the lubricity properties in these products. This requires new additive chemistry to fill the performance requirements in these products. Also, since sulfur acts as an effective antioxidant alternatives are more in demand.
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The reduction in sulfur using Groups II or III base oil, which are in wide use, does have the advantage of allowing formulators to control the level and type of sulfur additive compounding in the finished lubricant product. This also reduces the presence of active sulfur in the base oils which can form acids with the presence of moisture and other chemicals.
It seems high levels of sulphur are
bad news for cats, but seeing as Mobile one meets or exceeds ACEA A3/B3, A3/B4 spec, it can't be at problem levels. (Btw, it only has about 8% more sulphur than the Castrol).