i think draining them hot is better but with it sitting so long i would just drain it if i didnt have to start it. then maybe pour some mineral spirits down it with the drain plug out to get any gunk out. you might let it sit an hour or two for all the mineral spirits and old oil to get out.
Better to change oil hot or cold?
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I have always done hot drains. I want (hopefully) any particulates to suspend for the drain. Seems more complete and, well, just the way I have always done it.
Either way works. I'll let it drain longer when draining cold.
I compromise and drain while "warm". Still drains easily and no burned fingers.
I drain it hot. When it starts dripping instead of coming out in a line I pour some new oil in until the oil that's coming out of the drain plug changes color from the dark used oil color to the new oil color. Sometimes I do this with MMO since the difference is more obvious. When you start seeing new stuff come oil, plug it up and start filling.
Sorry to resurrect a thread, I'm probably going to [censored] someone off so I apologize in advance.
But correct me if I'm wrong, I thought oil (ex: 5w30) was a 5 weight at normal temps and a 30 weight at higher temps to protect the engine more. Right? So, if the oil is hotter the oil is HEAVIER and thus will be slower to drain out than if it was cold --- especially if the car was sitting overnight and all the oil had time to drain out of the engine.
So wouldn't it be better to change oil when it's cold? 1. All the oil is in the pan ready to drain. 2. The oil is at it's thinnest thus you'll get more of it.
Cuz if you heat it up, it's going to be all over the engine in a 30weight (more syrup like) and not completely drain out vs if you had it sitting overnight and it drained all off the engine.
I too grew up with people telling me to drain it hot because it would drain faster. But, how?! Hotter oil = heavier thicker oil? Am I missing something?
But correct me if I'm wrong, I thought oil (ex: 5w30) was a 5 weight at normal temps and a 30 weight at higher temps to protect the engine more. Right? So, if the oil is hotter the oil is HEAVIER and thus will be slower to drain out than if it was cold --- especially if the car was sitting overnight and all the oil had time to drain out of the engine.
So wouldn't it be better to change oil when it's cold? 1. All the oil is in the pan ready to drain. 2. The oil is at it's thinnest thus you'll get more of it.
Cuz if you heat it up, it's going to be all over the engine in a 30weight (more syrup like) and not completely drain out vs if you had it sitting overnight and it drained all off the engine.
I too grew up with people telling me to drain it hot because it would drain faster. But, how?! Hotter oil = heavier thicker oil? Am I missing something?
My opinion is that when the oil is cold, it is thicker, but not when under pressure in the engine. When pressure is applied it is thinner at cold temps hence the 5W, it is more viscous that way.
Just my .02
Just my .02
Straight 30 weight is much thicker than 5W30 at extreme low at around -25C, but 5W30 is about the same thickness of straight 30 at operating temperature at around 90-100C.
Read this,,,
http://www.bobistheoilguy.com/motor-oil-101/
5W30 and 10W30, 5W is thinner when cold than 10W. The reason to switch off between winter and summer for cold start up. Warmed up at operating temperature they are the same.
Hot oil along with all the contaminates drain better than cold oil.
Next time you deep fry french fries, drain the oil in the pan when hot, then next time let it set over night and drain the pan.
http://www.bobistheoilguy.com/motor-oil-101/
5W30 and 10W30, 5W is thinner when cold than 10W. The reason to switch off between winter and summer for cold start up. Warmed up at operating temperature they are the same.
Hot oil along with all the contaminates drain better than cold oil.
Next time you deep fry french fries, drain the oil in the pan when hot, then next time let it set over night and drain the pan.
OK so even though the oil is a 30 weight, it's THINNER at high temps than a 5weight oil at lower temps. Got it.
The whole 5 vs 30 weight thing just didn't make sense to me.
I'm running a 0w30 in my car right now. So 0 weight is supposed to be near water. 30 weight is a lot heavier. Thus it just seemed logical to me that draining the engine after a night would be better than spraying the engine with thicker oil.
But, I see now - at 290F+ the 30 weight oil is much THINNER than the 0 weight oil sitting in my garage at 95F. ?!
You'd think we'd call oil 30W0 then. lol
The whole 5 vs 30 weight thing just didn't make sense to me.
I'm running a 0w30 in my car right now. So 0 weight is supposed to be near water. 30 weight is a lot heavier. Thus it just seemed logical to me that draining the engine after a night would be better than spraying the engine with thicker oil.
But, I see now - at 290F+ the 30 weight oil is much THINNER than the 0 weight oil sitting in my garage at 95F. ?!
You'd think we'd call oil 30W0 then. lol
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Sorry guys, brain [censored]. Figured the first weight was true regardless of temperature.
Originally Posted By: OriginHacker21
I'm running a 0w30 in my car right now. So 0 weight is supposed to be near water.
A 0W-0 would be about like kerosene when hot but far thicker cold than a hot 50w...
A 0W-30 is like 30W hot and thinner than that same 30W when cold(but still far thicker than the engine needs)...
I'm running a 0w30 in my car right now. So 0 weight is supposed to be near water.
A 0W-0 would be about like kerosene when hot but far thicker cold than a hot 50w...
A 0W-30 is like 30W hot and thinner than that same 30W when cold(but still far thicker than the engine needs)...
Oil drains better when it's hot so it's good to let your engine warm up for about 5 minutes before changing it. But if the oil filter is in a retarded spot like under the exhaust, it's better to change it when the engine's cold. That way you don't burn yourself.
Originally Posted By: johnsmellsalot
Oil drains better when it's hot so it's good to let your engine warm up for about 5 minutes before changing it. But if the oil filter is in a retarded spot like under the exhaust, it's better to change it when the engine's cold. That way you don't burn yourself.
My filter is in a pretty retarded spot (Mercury Mystique 2.5L), but I find if I warm the car up and just let it sit and drain for 20 minutes, the exhaust pipes cool down and aren't a problem....
Oil drains better when it's hot so it's good to let your engine warm up for about 5 minutes before changing it. But if the oil filter is in a retarded spot like under the exhaust, it's better to change it when the engine's cold. That way you don't burn yourself.
My filter is in a pretty retarded spot (Mercury Mystique 2.5L), but I find if I warm the car up and just let it sit and drain for 20 minutes, the exhaust pipes cool down and aren't a problem....
Drained it cold for the first time.
Best answer.
Originally Posted By: pcoxe
I compromise and drain while "warm". Still drains easily and no burned fingers.
Since it was cold 10w-40 it was super thick, and it drained with less speed. Draining oil cold convinced me 10w-40 is too thick
Best answer.
Originally Posted By: pcoxe
I compromise and drain while "warm". Still drains easily and no burned fingers.
Since it was cold 10w-40 it was super thick, and it drained with less speed. Draining oil cold convinced me 10w-40 is too thick
I've noticed that I always get a lot more oil drained out when changing it cool, or rather after the car has not been run recently. Of course I only do that during the warm weather. In winter I change it while it's at least warm. Both my vehicles and my motorcycle usually get the oil changed in the morning after sitting all night. My bike hold 3 qts and 3 qts come out whan drained cool, 2.5 qts come out when hot. Honestly though as long as you are changing the oil on a regualr basis, I don't think it will matter much. I guess a good comprimise is doing it warm.
Ive always changed the oil hot. I was always told this growing up. You get a little bit less out because there is still oil on the engine components. You change it cold and all that oil has drained off of the components resulting in getting more oil, thus increasing the wear at the beginning of an oil change. It also enables the oil to pick up more contaminates and drain it get them out if its hot. Is this is all true or not, have no idea.
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