changing oil when hot or cold?

[heavyhaulerss]

when changing oil, does it matter if the engine has been off for a couple days, or does oil need to be at warmer temp before draining ?

[pdm]

Warmed up a little helps it drain better....but you won't go to jail if you don't....

[Kranky]

Run the engine for 10 or 15 minutes before draining the oil.

That will stir up any contaminants that have settled out of the oil, and the contaminants will then be drained out with the oil.

Sample the oil and have it analyzed. You'd be surprised at how much info this will provide on what's going on inside your engine.

[countryhorseman]

Follow the manufacturers guidelines!

But I am willing to bet, they all state to at least run the engine for 10-15 minutes as posted early, and for the reasons posted earlier!

Cold oil will stick to everything, and you will not get full benefit of the oil change!

[chubyboy]

yea let the engine warm up for awhile, in addition to a better cleaning, it drains faster and it will take less time to get an accurate reading on the dipstick when you add the new oil, as it will run through a warm engine faster. this applies to all vehicles, but personally, imho, i prefer the engine to be at normal operating temperature, while yes u get burned easier(u learn fast how not to ) it assures the fastest, most complete draining

[heavyhaulerss]

thanks for the replies

[9200IH]

This is just a opinion and I have no proof but I think if you shut a warm engine off and let it drain down into the pan and then drain the oil that has all gone into the pan after the engine has cooled you will get allot more old oil and contaminates out. If you start the engine and let it run for 10 minutes then drain it right away theres still a bunch of oil stuck to everthing that you won't get out.

I let my truck set over night, then drain.

If you really think about it, if you shut a warm engine off and let it completly drain over night if possible you will get more of the bad stuff out then if you start the engine run it for 10 minutes getting all the old oil and contaminates up top then draining it right away. There will still be allot of old oil up top when your tightening the plug.

[chubyboy]

but then you have to condier the metal shavings and sludge that settle out on the bottom of the oil pan while most of the oil runs right over it. while its warm and mixed, its in a solution and everything comes out, vs leaving seposits on the bottom of the oil pan

[9200IH]

Chubyboy I agree with you on that one. When the oil is hot it will wash everything out when you pull the plug.

[TheBigR]

After running all day when I get home and the oil is hot I drain it. I let it drain all night and in the morning I pull the filter and then put the drain plugs back on. A cold filter is much easier to work with and oil will not run out of it all over the place. Oil will drain from the top of the motor into the pan in 5 minutes.

[Kranky]

After running all day when I get home and the oil is hot I drain it. I let it drain all night and in the morning I pull the filter and then put the drain plugs back on. A cold filter is much easier to work with and oil will not run out of it all over the place. Oil will drain from the top of the motor into the pan in 5 minutes.

Punch a hole in the bottom of the filter and drain it before removing, and oil won't run out of it whether it's hot or cold.

Actually I've found that oil filters are easier to remove when warm, probably because the rubber gasket is more pliable when warm and it slides easier when twisting the filter off.