Oil Changing, Engine Hot or Cold???

[Brad S.]

Just have a really simple question.
When everyone changes oil are you doing it with a hot motor or cold? (At least whatever the outside temp is at the time)
Does changing oil with a hot motor get rid of more sludge???
Or what experiences have you had in this area??

 

['94IDITurbo7.3]

i change mine when the oil is warm.

 

[Knuckledragger]

X2 on warm. Usually after I have driven to work, about 9 miles, then let it sit for an hour or so. The oil flows easily and drains more completely.

 

[justinray]

I do mine whenever, ive never much concerned myself with it other than knowing the oil and filter are gonna be hella hot.

 

[icanfixall]

I only change after the thermostat has opened and I see the oil temp at 190 degrees on the gauge I have. Let it sit for 5 or 10 minutes and easily drain out the dirty. When it warmed up the oil will move easier out of the pan. We really never get all the dirty oil out. The oil cooler has plenty in it that wont drain out although it is on the block slanting towards the filter. We all know how much drains from the filter when we try to remove it....

 

['94IDITurbo7.3]

sometimes i will just pull the drain plug and filter and let it drain all night. next morning go out and finish it up.

 

[itsacrazyasian]

sometimes i will just pull the drain plug and filter and let it drain all night. next morning go out and finish it up.

The last time i left something loose on my truck resulted in disaster. Nothing with the truck's motor or trans thankfully.

 

[DesertBen44]

I do it with the oil piping hot. yeah it hurts but I think its better to drain it when hot

 

[stumpjumper3]

I always change the oil after the engine has been running at length at operating temp. I usually will take my center punch and punch a hole in the bottom of the oil filter to let it drain and then i will remove it.

 

[gdhillon]

what do you guys do to pull the filter off...it tried the belt method with no success. I assume a oversized filter wrench would do that trick

 

[dgr]

What belt method are you referencing? I use a strap wrench. I also use a psd filter so it has more length to grab onto. The strap wrench that takes a ratchet looks like it would work real well. By the way, in your other thread you wanted to reuse your oil filter. I would not do that after having an engine open and i would consider rebuilding the oil cooler opening up the engine.

To be contrary, i would say that changing your oil right after engine has ran would not get as much oil out vs. having the oil draining to the oil pan all night. But i would rather have some used oil coating everything when i start it and it has to pump a gallon of oil before the bearings start to see any oil pressure. So I change after a 10 minute warm up. Probably not a real concern with roller cams and15-40 oil

 

[rembrant88]

I learned to punch a hole in the filter after I drained it hot and while unscrewing the filter, besides burning my hands, the filter slipped and hit me in the head and covered me in hot oil. I almost knocked myself out cold when I panicked and hit my head on the frame.... Felt like an idiot and now I do it warm. True story .

 

[CDX825]

If you haven't ran it in awhile everything that's going to drain will be in the oil pan, so if you drain it cold your just waiting for the oil pan to drain. It takes a bit longer but you don't get burnt.

I'm also a fan of punching a hole in the filter with a small nail.

A Fumoto drain valve is also a good upgrade and makes the job quicker.

 

[Wyreth]

X2 on cold. Yes it takes longer for the pan the drain, but waiting for that just means there is time to have another beer while working on the truck!

 

[PwrSmoke]

Hot, or at least warm.

Why?

Because there are heat sensitive oxidation byproducts in used oil... namely varnish, which is similar to and a precursor to sludge. When hot, it's floating around in solution. When cold, it coagulates and stick to engine parts, eventually forming a coating. It will stay in the engine if you drain the oil cold. There was a great article in one of Noria's publications about this a few years ago. It isn't online that I could find.