Benefits of retained oil

[OilUzer]

background info:

I was reading a thread (posted yesterday) under mechanical & maintenance forum and the poster couldn't get to or forgot to change the oil filter ... anyways, couple of expert (? idk) guys were suggesting that:
"retained" oil is good ...
and there was no challenge ...
and I am going what the heck! ...

Background info part II:
One of the reasons I do my oil change is to get most if not all the oil out. I have seen dealer/quick lube places put the plug back while oil is still dripping.
I let it drip for 15+ min while doing other stuff and then bounce the car (the front) several times to get the last drops ...

Back to the story:
So I was curious about the leftover oil and had to do a search and found a year old bitog thread regarding this.
I read the very long & interesting page 1 and no immediate resolution in sight and many pages of back and forth some if not most over my head ... and i was hoping for a quick yes/no answer. Wishful thinking!

Question:
Not trying to rehash the old stuff but is there a consensus on this subject? new research or paper since last year? Experts Yes/No poll/percentage?

In a good way, i am learning some weird $hit on bitog. lol

Question 2:
I've had dealer/quick lube places forget to change the oil filter, they also leave some old oil behind and if you tell me over torquing the drain plug and/or oil filter/cap is ok, I may start using them again!

 

[JohnnyJohnson]

Originally Posted By: OilUzer
background info:


Question 2:
I've had dealer/quick lube places forget to change the oil filter, they also leave some old oil behind and if you tell me over torquing the drain plug and/or oil filter/cap is ok, I may start using them again!

Forgot or didn't have your filter in stock and just decided it was ok to not tell you and still charge you full boat? Never put money on what someone else did to your car or didn't while you weren't watching. There a reason they don't let you go into the shops anymore like they used to and it isn't all because of liability.

 

[4wd]

Originally Posted By: OilUzer
background info:

I was reading a thread (posted yesterday) under mechanical & maintenance forum and the poster couldn't get to or forgot to change the oil filter ... anyways, couple of expert (? idk) guys were suggesting that:
"retained" oil is good ...
and there was no challenge ...
and I am going what the heck! ...

Background info part II:
One of the reasons I do my oil change is to get most if not all the oil out. I have seen dealer/quick lube places put the plug back while oil is still dripping.
I let it drip for 15+ min while doing other stuff and then bounce the car (the front) several times to get the last drops ...

Back to the story:
So I was curious about the leftover oil and had to do a search and found a year old bitog thread regarding this.
I read the very long & interesting page 1 and no immediate resolution in sight and many pages of back and forth some if not most over my head ... and i was hoping for a quick yes/no answer. Wishful thinking!

Question:
Not trying to rehash the old stuff but is there a consensus on this subject? new research or paper since last year? Experts Yes/No poll/percentage?

In a good way, i am learning some weird $hit on bitog. lol

Question 2:
I've had dealer/quick lube places forget to change the oil filter, they also leave some old oil behind and if you tell me over torquing the drain plug and/or oil filter/cap is ok, I may start using them again!

Some strong supporters here wrt deposition of AW compounds … but if so, does that favor a long OCI (all things considered)
-vs- the 1/2 quart I retained in a dirty and potentially failed oil filter …
Question 2: change your own oil all you can …

 

[JoelB]

I don't know the effects of leftover oil. But I can tell you to give up on the idea of getting "all the oil" out of your engine during an oil change. There will always be residual oil in the block. Unless you were to tear it apart and brake clean all the surfaces there will be old oil left over. That's why i don't bother waiting until it stops dripping. Big picture it makes no difference if you drain for 2 minutes or all night.

 

[LotI]

Originally Posted By: JoelB
I don't know the effects of leftover oil. But I can tell you to give up on the idea of getting "all the oil" out of your engine during an oil change. There will always be residual oil in the block. Unless you were to tear it apart and brake clean all the surfaces there will be old oil left over. That's why i don't bother waiting until it stops dripping. Big picture it makes no difference if you drain for 2 minutes or all night.


For a point of reference, my last Honda Accord with the K24 engine lists 4.4qts of oil needed during and oil and filter change.

The dry fill on a new engine is 5.7qts.

25% of the oil in the engine is from the previous fill. No bouncing of the car will get it out.

The OP asked if there was some new research on this...not that I’m aware of. There have been references to an older SAE study showing that wear decreases with time during oil use. AW compounds become more effective and the filter becomes more effective is the summary. I don’t have a subscription so I can’t reference it.

 

[46Harry]

I always let my oil drain for a few minutes after I pull the drain plug, but I know there is oil hiding in many places inside of the block which will not come out unless the engine is completely torn down. I don't think that whatever residual oil that is left in the engine makes any difference in engine longevity.

 

[4wd]

Originally Posted By: LotI
Originally Posted By: JoelB
I don't know the effects of leftover oil. But I can tell you to give up on the idea of getting "all the oil" out of your engine during an oil change. There will always be residual oil in the block. Unless you were to tear it apart and brake clean all the surfaces there will be old oil left over. That's why i don't bother waiting until it stops dripping. Big picture it makes no difference if you drain for 2 minutes or all night.


For a point of reference, my last Honda Accord with the K24 engine lists 4.4qts of oil needed during and oil and filter change.

The dry fill on a new engine is 5.7qts.

25% of the oil in the engine is from the previous fill. No bouncing of the car will get it out.

The OP asked if there was some new research on this...not that I’m aware of. There have been references to an older SAE study showing that wear decreases with time during oil use. AW compounds become more effective and the filter becomes more effective is the summary. I don’t have a subscription so I can’t reference it.


1) something to think about when doing UOA too early on new engines
2) I have poured a half quart through with plug out ... clean oil came out ...
3) BiL’s Chevy did 400k on bulk Mobil conventional (5k) from a Mobil 1 quick lube

 

[Zee09]

You're supposed to shake the car at all four ends of the body while the drain plug is out.
That removes all residual oil

 

[OilUzer]

Believe it or not why I "shake" it after drips have almost stopped, i get another stream and ... drips ... for additional 30-60 seconds!

 

[Wylie6G72]

The drain plug on my '15 Canyon is on the passenger side of the pan, so I drive the driver's side up on stacked 2x4s, pull the plug, and let it drain for about an hour. What's left after that is just going to have to stay there.

 

[CT8]

O.K. what ever. There is an oil film left when changing the oil.

 

[KGMtech]

Originally Posted By: OilUzer
Believe it or not why I "shake" it after drips have almost stopped, i get another stream and ... drips ... for additional 30-60 seconds!

That's a comment to another personal health issue....using Flowmax?

Tap it twice and zip, any more and you're playing with it )

 

[ridgerunner]

I actually drain the oil and let it drip for a half hr then I start the engine a couple of times for a few seconds and more oil comes out. Only do this with my 3/4 ton truck since it has an oil cooler.

 

[WyrTwister]

Kind of like a transmission dump & fill . Some where around 1/2 the fluid is still left in the torque converter .

TQ's used to have a drain plug , at least on some of them . I do not know of any that do now .

At least all of my vehicles have a drain plug on the engine oil pan . Do not have to vacuum the oil out via the dip stick tube ?

 

[mjoekingz28]

Time to ban this nasty Canadian

 

[mjoekingz28]

Originally Posted By: KGMtech
Originally Posted By: OilUzer
Believe it or not why I "shake" it after drips have almost stopped, i get another stream and ... drips ... for additional 30-60 seconds!

That's a comment to another personal health issue....using Flowmax?

Tap it twice and zip, any more and you're playing with it )

 

[mjoekingz28]

If the antiwear additives from old oil help the new oil change, then it seems running a 15-20k mile oil for 7500 miles is counter-productive.

I used to wait til it quit dripping. Now-a-days I insert the plug just as it starts to drip. I think there are like 1700 drops of oil in a quart, so guessing that by leaving the plug out over night or any time after it goes from a continuous flow to drops would net you like an ounce or two. Not really worth it if you ask me.

And I like to get under the vehicle once and be done. Not going back and forth and up and down. Just have a clean rag handy and you can wipe stuff clean as you inspect the underbody for a minute or two while she drains. It peeved me sometimes when I would be all set to go underneath, then have to get back up to get a washer, drain pan, tool or whatever I forgot to lay out for the underside part of the job

 

[CT8]

Originally Posted By: JoelB
I don't know the effects of leftover oil. But I can tell you to give up on the idea of getting "all the oil" out of your engine during an oil change. There will always be residual oil in the block. Unless you were to tear it apart and brake clean all the surfaces there will be old oil left over. That's why i don't bother waiting until it stops dripping. Big picture it makes no difference if you drain for 2 minutes or all night.
+1 The voodoo people do thinking they are doing good is simply amazing

 

[Whipcitywrencher]

Originally Posted By: ridgerunner
I actually drain the oil and let it drip for a half hr then I start the engine a couple of times for a few seconds and more oil comes out. Only do this with my 3/4 ton truck since it has an oil cooler.



I wouldn't do this, dry starting your engine.
Good way to mess up your crank and rod bearings.

 

[Tdog02]

Get out as much as you can, fill and take off. Everything will not come out, it's just not possible. No worries, change with quality oil on a regular basis and your engine will go until something breaks. It really is that simple.

shooting for 300,000 miles in my rides