Oil changes: Warm or Cold?

[CobyRupert]

Does it matter if oil changes are down with a warm or cold engine?

Not sure if this has been debated here on TBN. There seems to be a wide debate on the internet.
I know the difference is miniscule in the big picture, and this is mostly an academic debate, but let's argue anyways.....

For 30 plus years, I've always warmed the engine prior to changing oil, mostly because I'm in a hurry.

My tractor is due for an oil change, and I just don't feel like (cold) starting it up for 10-15 minutes unnecessarily. (I'll probably compromise and plug in the block heater prior to draining, or just wait until after next time I use it). Assume in both cases, that one let's the oil pan drain for a >1/2 hour.

Cold:
Pros: Don't have to do one (1) unnecessary cold start.
More oil gets drained. Most of it ran down when oil was warm from the last time I ran tractor (Same as a hot oil change). However one would think that additional oil that has the extra time to run down to sump also gets drained.
Con: Particulate (metal shavings) that are setting on bottom of oil pan may not get drained because they aren't re-suspended in the oil like a recently run engine. But shouldn't they be in filter anyways?

What are other pro/cons to each method?

 

[tcreeley]

Warm engines drain faster, and carry any gunk with them more easily. They also drain more thoroughly.

But if you do regular oil changes with new filters, I don't think it matters. If I am changing the oil and its 15F - then I warm the engine so that the engine oil will flow more easily.- This is more important the thicker your oil is.

 

[Agvg]

Do you get the oil temp high enough if you run it for 10 - 15 minutes? And engines are made for cold starts, see a lot seems to think this is an issue but I can't quite understand the problem, the extra wear are more or less just a academic debate and not an real problem.

 

[Industrial Toys]

I would opt for warm, but then some oil is still on many surfaces, and will eventually run down. So maybe warm, but wait an hour after shutdown.

 

[deserteagle71]

I NEVER change the oil in any of my vehicles unless the engine has been run for a good long while and everything is hot. I want all the crap that may have settled out of the oil thoroughly suspended in the hot oil and drained out of the engine.

 

[Industrial Toys]

I'd like to be able to open a spigot when someone is tailgating me.

 

[dalola]

I NEVER change the oil in any of my vehicles unless the engine has been run for a good long while and everything is hot. I want all the crap that may have settled out of the oil thoroughly suspended in the hot oil and drained out of the engine.

Totally agree...... Not cold, not warm, HOT! Otherwise, you're leaving more stuff behind.

 

[jaxs]

The best way is the one that make's you feel best.:confused3:

 

[Jstpssng]

I'd like to be able to open a spigot when someone is tailgating me.

Preferably not with oil currently in your crankcase.
I watched an old 1954 movie about moonshine runners where the hero did that to a couple of thugs who were chasing him. He had a tank in the back and a valve that released the oil, much like the tar trucks you see on paving jobs.

 

[oosik]

I think Jaxs has hit the nail directly on the head. " Do it which ever way makes you feel best". Man - its a SLOW day at the fish market!!!!