This was good. Shows the crazy long drains are not impactful. 50ml = .05qt. Complete waste of time.
Letting Oil Drain Overnight
- Thread starter garageman402
- Start date
This was good. Shows the crazy long drains are not impactful. 50ml = .05qt. Complete waste of time.
I have a Fumoto valve, when I had my house I would start the drain before it got dark, wake up the next mourning and close valve, replace filter and fill oil. Now no house… I pump out the oil and replace oil filter every other change. I don’t think a half cup of oil oil left in the engine is going to kill it.
The amount of oil left in the engine oil galleries, oil pump and under the valve cover in the nooks and crannies after the draining is down to drips, is minimal. Maybe 1/4 quart. If the oil looks dark after a change, you let it go too long and you probably should change it more often.
This is how it should look after running a few minutes after a change,
For some reason I found that I couldn't drain as much oil with the Fumoto valves on two different cars. The valve reduces the diameter of the drain hole and more oil is left in the bottom of the pan. Plus, they drain slower. Personally, I think they are only useful if you have a car that is really hard to get at the drain plug. I have to raise the car anyway to get the filter off so it is very easy to just pull the drain plug.
dnewton3
Staff member
There is no documented proof (SAE or OEM credible study) I'm aware of showing that the duration of the oil change has any bearing on the operational lifespan of the engine.
There is, however, reasonable anecdotal evidence from the MILLIONS of vehicles which get oil changes at dealerships and quick-lube places every year indicating that the hours of "drip-drip-drip" is moot. If it were detrimental to engines to not let them drain longer than a few minutes, we'd see metric tons of dead cars and trucks strewn all over our roadways.
It is the BITOG way to try to eek out every last effort to get the "best" for your baby.
It's also the BITOG way to be overzealous and waste time/effort/money on stuff which has no proof of concept; it satisfies an emotional desire only.
There is, however, reasonable anecdotal evidence from the MILLIONS of vehicles which get oil changes at dealerships and quick-lube places every year indicating that the hours of "drip-drip-drip" is moot. If it were detrimental to engines to not let them drain longer than a few minutes, we'd see metric tons of dead cars and trucks strewn all over our roadways.
It is the BITOG way to try to eek out every last effort to get the "best" for your baby.
It's also the BITOG way to be overzealous and waste time/effort/money on stuff which has no proof of concept; it satisfies an emotional desire only.
4WD
$50 site donor 2025
Same way I feel about exposing my skin to scalding hot oil or hot metal. Come off fast idle - up the ramps - change oil warm …
Honestly I don't really think that's at all necessary.
Draining oil overnight is just waste of time and if its done to a cold engine, not ideal either. You want engine warmed up to temperature because oil will drain faster and also all the sediments/contaminants in the engine will be whipped around and mix with the oil and most of it will be drained away with the oil. In a cold engine the sediments will settle at the bottom and might not even drain away even overnight.
I put mine on ramps when I get home on a Friday night and let it drain til Saturday morning. Pre-fill the filter, pour in the oil and start on my other weekend chores.
I open the drain plug and the oil drain out till it drips about once per 5 seconds. Change filter, prefill and install. I would never leave my car drain overnight since I may need it for an emergency surprise.
I’ve always done cold drain. I understand that hot oil drain faster. But walk me through this hot drain gets more contaminates out. You drive a vehicle around so the engine is hot. You shut it off and the oil settles in the pan for 30mins. All the contaminants are now in the oil, right? But then let it sit overnight - aren’t the same contaminants still in the oil the next day? They are certainly not crawling back up into the engine overnight.
When taking an oil sample, it is good to do it hot because it mixes everything up so you get a good, even sample. Contaminants settle to the lowest point due to gravity and can alter results.
But how is one exactly getting more contaminants “out” with a hot drain vs cold?
My grandpa and my dad used to do that, in fact my grandpa would even jack the car up a little on the side opposite to the drain plug!
I can't be bothered, i let it drain for maybe 15 minutes.
I can't be bothered, i let it drain for maybe 15 minutes.
Fair point, you never know when you might have to go in a hurry, unless you have another vehicle.
Moreover, the risk far outweighs any perceived reward. What if you need the vehicle in the middle of the night because of an emergency? Gotta finish an oil change at 2am while your spouse sets there with a broken arm before you head to the hospital to get it looked at. That sounds like fun.
When you put sugar into tea or coffee you give it a stir right? Same idea. When oil is circulating the sediments/contaminants will be picked up and mixed with the oil and thus be drained away at the oil change, most of it at least.
I don’t think that analogy works. Sediment goes to the lowest point due to gravity which in this case would be the drain. I don’t know anyone who would advocate drinking unmixed tea from a drain in the bottom of the cup. Seems like a logical fallacy.
I think VW came up with a guideline when to reinstall the drain plug when doing an oil change. I can't remember it. Six seconds between drips or something.
My process ritual:
1) drive ~15 miles
2) on return, go right up the ramps
3) remove drain plug and let drain til about 1 drip per 5 sec. Hand tighten drain plug
4) remove filter
5) spend time wiping down oil from filter and drain pan areas and any other areas oil has migrated to.
6) go in the house and have some lunch or a drink (~15-30 min)
7) come back out, remove drain plug and let whatever has accumulated drain until we're back to about 1 drip per 5 sec.
8) Torque drain plug down
9) add a small amount of fresh oil into new filter and screw it on.
10) one more visual inspection and wipedown of entire area.
edit: when you reopen the drain plug, the oil that's accumulated comes out in a more satisfying stream rather than a slow drip. It helps me feel like more has come out.
Also, I make sure I'm being productive between step 3 and step 7. I'm doing other things to the car that I'd be doing anyway, and taking advantage of that time to get a little more old oil out, which I can then watch come out at step 7.
1) drive ~15 miles
2) on return, go right up the ramps
3) remove drain plug and let drain til about 1 drip per 5 sec. Hand tighten drain plug
4) remove filter
5) spend time wiping down oil from filter and drain pan areas and any other areas oil has migrated to.
6) go in the house and have some lunch or a drink (~15-30 min)
7) come back out, remove drain plug and let whatever has accumulated drain until we're back to about 1 drip per 5 sec.
8) Torque drain plug down
9) add a small amount of fresh oil into new filter and screw it on.
10) one more visual inspection and wipedown of entire area.
edit: when you reopen the drain plug, the oil that's accumulated comes out in a more satisfying stream rather than a slow drip. It helps me feel like more has come out.
Also, I make sure I'm being productive between step 3 and step 7. I'm doing other things to the car that I'd be doing anyway, and taking advantage of that time to get a little more old oil out, which I can then watch come out at step 7.
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