SaVaGeEaRL wrote on 09/22/12 at 19:10:15:I change mine cold. It's thinner when it's cold.
No it isn't. Those numbers in the oil weight, like 10w40 are defined by the SAE tests on how the oil pours at low and high temperatures.
Translated, they say the oil does pour quicker hot than cold.
I have done the freezer test on T-6 and while it doesn't change nearly as much as old dino oils did, but it is a little bit thicker pouring at -10 degrees F than it is at room temperature. The temp/viscosity change is there for full synthetic T-6, just not nearly as much as the old dino 10w40 oils used to have.
Do it yourself if you want to .... we all got us a freezer at home and we can time how long it takes to pour out a fixed amount like a test tube full.
Now, at room temperature vs engine warm, the drain rate difference is still there, but not nearly as pronounced.
And yes, you can drain your oil successfully at room temperature. The few extra seconds it takes to drain isn't so much time as to be all that noticeable. Your drip time to zero drops will be greater though.
I think the old saw about "drain your oil hot" came from dino oils back in the age of sludge, when you wanted to melt as much of the sludge as much as you could so more of it could get out of the little drain hole and into the drain pan.
Modern oils don't form sludge (at least my T-6 has never formed any).
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Here is some visual data on oil thickening at lower temperatures and room temperature.