Extreme extended drain time: How much oil drips out over a week?

[puellarum]

That won't flush much of the old oil out because the old oil is dispersed throughout the engine. High spots and low spots, front and back. The pint will take the gravity path of least resistance. Might get 1/10 of it out or something like that.

If you're that concerned about it, then drain the oil. Leave the filter. Refill thr crankcase. Crank it and let it run for 5 minutes. Then drain it all again, including the filter.

OR, take a deep breath. Move beyond your OCD and just change it all normally and don't worry about the dripping at the end...

 

[Wingo]

I'm surprised some don't pour a sacrificial quart of fresh oil to push out that 3oz of residual bad oil.

I don't do it for engine oil, but I do a little flush with a few ounces of clean gear oil when doing differentials.

 

[Jpc1623]

Winter drain is extracted thru the dip stick. Summer drain thru the plug. Open plug get a cup of coffee, donut, play with grand kids. Go back out finish the job.

 

[Bighorn2500]

Usually however long it takes to rotate four tires (20 minutes roughly) while the vehicle is in the air for me is how long it drains for.

 

[Faawrenchbndr]

Like many things, I greatly overthink stuff. I have left a drain plug out for about an hour before.
It would drive me NUTS to have a plug out for a week.

 

[TiGeo]

Nice! I try to let mine get to a slow drip.

 

[Redhawk454]

Depends on the engine. Oil stays up on the top half of the engine for a long time.

 

[ATex7239]

Oil change edging

 

[Snagglefoot]

And then the wife hops in and drives down to the mall for some baking soda.

 

[hemioiler]

Doesn't everyone suck it out with a vacuum cleaner like me? Thought I was odd ...

(just kidding, I wait for the drip and put the plug back in. my oil changes are always done at 5000 to 7000 miles so the oil left behind is still in good condition anyway.)

 

[spk2000]

Great information that some including myself have wondered. Thanks for proving this out.

 

[Bill_W]

The whole idea of an oil change is not to let the engine set after the warm up for drain. There is plenty of lube in the engine for it to turn over to get the new oil circulating. Allowing the oil to drain for a week and starting up is a very bad idea.

 

[oldgrayman]

The whole idea of an oil change is not to let the engine set after the warm up for drain. There is plenty of lube in the engine for it to turn over to get the new oil circulating. Allowing the oil to drain for a week and starting up is a very bad idea.

How is it any worse than just letting the vehicle sit for a week ?

 

[Allaneddie]

Thanks to the OP for doing this and posting. Won't change much of what each of us is already doing but does give some interesting information about what is old oil is left in engine with most oil changes.

 

[TumblrDucks]

I did not want to start a new thread but I did test this. Overnight or over a whole week (what this sample is) would be the same which doesn't amount to much oil to make any difference. Car was a 2007 Mkz 153,000 miles, Quaker State 5w-30 Synthetic is what came out @ 8,000 miles on oil. Car was supported at front with jackstands rear tires on ground, drain hole facing rear of vehicle. After initial drain and couple minutes of drip I put a water bottle under and came back to my shop one week later. This is what it collected:


View attachment 194731

View attachment 194732

Under 3oz.

Thank you for the time and patience. It's good to know!

 

[ATex7239]

And then the wife hops in and drives down to the mall for some baking soda.

[Husband’s cell phone rings]

Husband: Hello.

Wife: Hey sweetie, I had to run to the store this morning… but um, the car… it is kind of making a funny noise and acting weird… and I think the… uh, genie’s lamp light is on?

Husband: Dear God… [hangs up phone]

Husband: [Immediately opens up BITOG, goes to the General Auto Sub and starts a new thread]

 

[dubber09]

You can wait a week for old oil to drip, sludge will stay in oil pan thou, there is absolutely no point to do this.
Change oil on regular basis with reasonable OCI, use good oil, that's all.

 

[cryptolyme]

probably better for the engine to not let it drain completely. that way you don't have a dry start.

 

[gfh77665]

If you're that concerned about it, then drain the oil. Leave the filter. Refill thr crankcase. Crank it and let it run for 5 minutes. Then drain it all again, including the filter.

OR, take a deep breath. Move beyond your OCD and just change it all normally and don't worry about the dripping at the end...

I am not at all concerned about it. I don't do this at all. I was just responding to other posters. I have no OCD. In fact I advocate for changing filters every other oil change.

 

[CR94]

Interesting experiment. That 3 ounces is small, compared to the amount of trapped oil that would never drain even if you leave the plug out for a year.