More cold start noise at 10F with 5w compared to 0w

Started my J35 at -5 degrees today. My power steering pump groans at low temps, and there's certainly more noise from under the hood upon start-up in general at these temperatures.

I'm running 5W-30 Mobil 1 EP High Mileage right now, and I don't think the oil is the issue, I think it's that all of the pulleys/accessories need to warm up too (the oil coating inside of the bearings in the pulleys/idler for example) and also that every single piece of metal in or attached to the engine is at it's smallest size due to thermal contraction, leaving more space between all moving parts than usual, allowing more vibration/noise. That's my theory anyway.
awesome ty, i feel the same way and nice to hear an opinion of of a fellow j35er. neat to see another 5w-30 user in a cold ish weather
 
VRP 5W-30 is fairly thick, with a high KV40 and a low viscosity index. Here's a chart comparing its kinematic viscosity with a higher-VI 0W-20 (Pennzoil Platinum). The VRP has around twice the viscosity. The difference is equivalent to 9°C / 16°F, which is pretty significant.

Technically, KV is not the most relevant viscosity metric at these temperatures. A CCS measurement at the actual temperature of the oil would be more relevant, but the point is that there could be a fairly large difference, especially since the VRP is thick at low temperatures for a 5W-30.

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thanks v much! i used to think of this methodology but i was told that this is incorrect as we have to factor pumpability and crankability and apparently at these temps the oil pump will pump/crank them both almost equal. this is why saw j300 is a spec etc?

when i used to think of oil as a projectfarm type of thinking, i would always be corrected.

do you have any insight on the above?
 
It sounds like the dreaded VTEC cam gear rattle. Thicker oil, whether due to a different grade or colder environmental temperatures, will make it worse.
 
when i used to think of oil as a projectfarm type of thinking, i would always be corrected.
Project Fram "cold oil races" doesn't always represent CCS (cranking) and MRV (pumpability) behavior. If people want to determine the best very cold start-up W rated oil, they need to compare the actual CCS and MRV dynamic viscosity (cP units) specs for each oil.
 
well said ZeeOSix,,this factor of testing MRV and CCS is more important for cold weather performance of the oil , pour point is only a indirect reference to this also.many manufactures neglect to publish the CCS and MRV test results unfortunately.
 
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