Are synthetic oils of the same grade thinner?

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As a general rule of thumb, are synthetic oils of the same grade thinner than their comparable conventional counterparts? Would this be a rationale reason therefore to go up a grade when switching to a synthetic? ie. since they're more slippery and all...
 
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Canberra ACT Australia
Yes and no. Try this, Castrol Formula R 5W30 'synthetic' is 12.2cSt @ 100C and Fuchs Super GTO 10W30 MC (PAO) is 12.5 cSt @ 100C. But the Castrol has zero PAO or ester (I asked yesterday) so it's kinda hard to answer. And yes Castrol are bastard's for selling the above oil for A$62 per 5 litre jug nearly the same price as M1 SS 5W50.
 
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quote:
Yes and no. Try this, Castrol Formula R 5W30 'synthetic' is 12.2cSt @ 100C and Fuchs Super GTO 10W30 MC (PAO) is 12.5 cSt @ 100C.
sprintman are those oils rated ACEA A3? I think almost any synthetic oil that is rated ACEA A1/B1 or A5/B5 will be thinner than almost any conventional oil that is rated ACEA A1/B1 or API SL or SJ and is of the same viscosity grade. A 30 weight oil that is rated ACEA A3 or B3/B4 will have an HT/HS viscosity, cP @ 150 C >3.5 and as a result of this will be significantly thicker than a 30 weight oil that is not blended to meet this requirement. [ November 04, 2003, 07:30 AM: Message edited by: Sin City ]
 
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