Should I leave a little used oil in? ( DNewton3 )

[Triple_Se7en]

I quit changing scolding hot oil filters. I now change them cold, then run the engine hot to change the oil.
Matters-not that the filter now contains several ounces of old oil..... no big deal and my dipstick still always shows crystal clear for over 1K of the next OCI.

 

[Patman]

Originally Posted By: Triple_Se7en
I quit changing scolding hot oil filters. I now change them cold, then run the engine hot to change the oil.
Matters-not that the filter now contains several ounces of old oil..... no big deal and my dipstick still always shows crystal clear for over 1K of the next OCI.


If I wasn't taking samples for UOA, I wouldn't even be doing an oil change on a hot engine. I changed the oil in my wife's BMW on Saturday morning and since I wasn't going to draw a sample, I only drove the car a couple of miles just to get the oil a little bit warmer since it was below the freezing mark at the time (if it was 60-70 degrees outside I wouldn't have even driven it at all) It was a much better oil change experience not having the oil scalding hot. My old method a few years ago was always to drain the oil after a very long drive, take a sample for UOA and then let the oil drain for an hour or two in order to cool things right down before I changed the filter. But I haven't done that method in a while.

 

[irv]

Originally Posted By: Triple_Se7en
I quit changing scolding hot oil filters. I now change them cold, then run the engine hot to change the oil.
Matters-not that the filter now contains several ounces of old oil..... no big deal and my dipstick still always shows crystal clear for over 1K of the next OCI.


Why not just drain the oil then tackle the filter a few minutes later? I don't understand the rationale of having to change the filter immediately after undoing the oil pan drain bolt?
If my filter is still too hot, I give it a bit more time but truthfully, after a few minutes of draining, the filter, although still hot, isn't so hot I can't handle it.

 

[BrocLuno]

Originally Posted By: dnewton3
To the OP -

No, don't leave in some portion of used oil. Either leave it all in there, or change it.

OCIs do NOT induce a death-march of engine wear. Fresh oil does degrade the TCB; that's proven. But it's not harmful by any means.

My data, and the SAE studies, show that longer OCIs are very safe in terms of wear rates. But do NOT take an approach as to assume that if one direction is safe, the other is unsafe; that is untrue.

The concepts to glean are this:
- longer OCIs are safe; the wear rates are very low out to 15k miles
- shorter OCIs do not benefit with lower wear rates; they exhibit a higher wear rate (although not an unsafe one)

Folks that OCI frequently seem to believe that is something is good, more must be better. Changing oil more often, is neither helpful nor hurtful. Unless you count the pain in your wallet from throwing away perfectly functional fluids.

If you're going to OCI, then do so. Don't "partial it". If not, leave it alone.


Nope, I'll do it my way to save my back. The engine is already over 200,000 miles and running happily. It's all about me. It's easier to change the filter from the top with the vehicle on the ground (not ramps). Easier to position the catch pan, etc. (especially the JAG).

So I change my filter this time if I'm doing upper services and few weeks later I change the oil when it's up on ramps and it's a nice day out (cold change). All my vehicles seem to be this way...

This thread has made me re-think the need to be OCD about changing both at the same time. Since the wear metals are so low with used oil, there is little for the filter to do. And yes, it will have one qt of used oil plus sump corners, etc. So what? 85% new oil (Drain & Fill, plus dilution of one qt at filter change top-up) will carry the motor another round of 7~10K easily

 

[BrocLuno]

Originally Posted By: userfriendly
So if "wear metals" are not actually wear metals, why test for them?


Because they are source metals from somewhere... They offer service to help the maintenance staff find problems and fix them before they wreck an engine. Sometimes they are wear metals. Sometimes the reaction metals. In either case, they have some meaning in finding a problem.

 

[demarpaint]

Originally Posted By: irv
Originally Posted By: Triple_Se7en
I quit changing scolding hot oil filters. I now change them cold, then run the engine hot to change the oil.
Matters-not that the filter now contains several ounces of old oil..... no big deal and my dipstick still always shows crystal clear for over 1K of the next OCI.


Why not just drain the oil then tackle the filter a few minutes later? I don't understand the rationale of having to change the filter immediately after undoing the oil pan drain bolt?
If my filter is still too hot, I give it a bit more time but truthfully, after a few minutes of draining, the filter, although still hot, isn't so hot I can't handle it.


Exactly. I drive, get the engine good and warm and run it up on the ramps. Go inside for a few minutes, come out and pull the drain plug. I'll either do some yard work, clean the garage, or make a few phone calls while the oil drains. About half an hour later, sometimes longer I'll remove the oil filter, pre-fill the new filter and install it, put in the drain plug, and refill the engine with oil. My Liberty's oil filter is in a PITA location so for that one I'll wear a heavy rubber glove with a grip texture to get it out. Never a problem that way, and it is not too hot to handle.

 

[Malo83]

Originally Posted By: Dallas69
Just change the oil and filter man.
You already put 11000 on it and that filter is shot unless its an Ultra.
You worry too much.

X2, change it all out,oil-filter

 

[Linctex]

Originally Posted By: Malo83
Originally Posted By: Dallas69
Just change the oil and filter man.
You already put 11000 on it and that filter is shot unless its an Ultra.
You worry too much.

X2, change it all out,oil-filter

I have absolutely ZERO interest in your conjecture, beliefs, rumors your grandmother told you, what "old Joe at the local garage" told you, etc. etc. etc. etc etc.

At least make SOME sort of attempt at logic, reason, or science before posting.

 

[jakewells]

My old truck ( see signature ) between the oil burning and rear main leaking some. I just change the filter and top off the oil usually two quarts at a time.
The dirtier the oil the less it consumes and it is more quiet that way which is little odd. I have ran supertech st8 filters to 10,000 before usually changing them, I only really change oil when it feels gritty between my fingers.

 

[Revving2Redline]

I change oil every 10k when the OLM gets 10 to 15 percent. Since this engine has lived mostly on Hbn like ceratec,archoil9300 or Mos2 will I have/see lower wear changes during Oci?

 

[andyd]

The engine was designed for passenger use, not an 11" clutch. I had a few 223s The original in the '62 F250 threw #6 rod and it broke the last 2 lobes off the cam when it exited the block.

 

[BrocLuno]

Well they sold it that way, so it was an OEM system ...

This thread has wandered some, but it has been a robust discussion

I guess those of us who leave some at change time (usually a filter full), and those that have to do both are just going to be in different camps ...

Camp Some and Camp All ~ but we know it's not really "all" ...

So it's really some oil changed (say 80%) and more oil changed (say 95%). Unless a new rebuild, it's never all oil changed.

So what we are discussing is: How much residual is the right amount?

I say a filter full and some here and there (Camp Some). dnewton says all but the some here and there (Camp All).

For those that change both oil & filter together, what say you to the FACT that filters work much better after time in use?

Where is the real bottom line here on retained oil and partially used filters?

 

[CT8]

This leaving in some oil is about as foolish as DR Hass writings that people regurgitated as fact for years. Lets say then a Frantz filter with a tp change and a new quart of oil every 2000 miles [ A complete oil change at 10,000 miles in a 5 qt sump]should make an engine last forever? Come on guys . Remember it is AMSOIL not Amsoil

 

[BrocLuno]

Nope, my keyboard refuses to write all caps ...

Unless you tear an engine down completely, you always have some residual oil. What are you going to do, drop the pan and wipe down everything ... It's a matter of how much oil is retained being discussed here ...

The OCD crowd is not liking this thread at all. So ...

 

[Virtus_Probi]

This is confusing me so much that I'm just going to trade my cars in and buy new ones whenever oil change time comes around.

Question is, is that 5k, 10k, 15k, 20k...???
Wait, some people say to change the oil at 1k to get the shavings out...

AAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHH!!!!!!

 

[Shannow]

Originally Posted By: Virtus_Probi
This is confusing me so much that I'm just going to trade my cars in and buy new ones whenever oil change time comes around.

Question is, is that 5k, 10k, 15k, 20k...???
Wait, some people say to change the oil at 1k to get the shavings out...

AAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHH!!!!!!


Per Mechanics Illustrated back in the day (a LONG time ago), Ford approached Castrol for an oil to put in their 25,000 mile disposable car that they were considering...wanted an oil that would go the distance.

Answer back was 25,000 miles...our oil is fine for a disposable car.

 

[Virtus_Probi]

Originally Posted By: Shannow

Per Mechanics Illustrated back in the day (a LONG time ago), Ford approached Castrol for an oil to put in their 25,000 mile disposable car that they were considering...wanted an oil that would go the distance.

Answer back was 25,000 miles...our oil is fine for a disposable car.

Very interesting post...I guess I can see that if you really don't care about the car going past 25kmiles, anyway.
Who cares if you notice some sludge just as you are tipping it into the landfill??

 

[BrocLuno]

OK, if we assume that some maintenance is better than no maintenance, then it comes down to how much and when?

This thread is about the benefits and side effects of some retained oil at change time.

dnewton wants us to take the oil out to nearer the limits of its usable lifespan. I want to service when it's convenient to me. The engine does not care as long as the lube is serviceable.

So BITOG'ers know about good lubes, good filters, etc. Seems most don't want to push anything to far and I find that sensible. W/o spending the cost of an oil change on a UOA, it makes no sense to extend anything beyond 10,000 miles. And some engines will destroy their oil well before that (fuel dilution, other contamination, etc.).

So what is really going on in this thread is to see if folks can get their head around the FACT that some retained oil is OK, and may have some benefit... So that means that do-it-yourself backyard services can be done in convenient way, filters can be left in place for two or three cycles, etc. No harm done

Folks buy premium filters and toss them at 5,000 miles. Makes no sense. Folks put premium oils in that can go a long time (past 10,000 ...) and drain them at 5,000 miles. Again, makes no sense.

But it feels right to them, so they do it ... Here we are going back and forth on other strategies. And you'all can see the results

A LOT of BITOG is about emotional input to vehicle maintenance. I'm just as guilty as the next person. I have done 3K changes. And left oil in for 5 years. The engines did not care. It was something I did for me.

This thread is just about expanding the range of maintenance responses to fit the owners lifestyle or business needs to get the most out of a vehicle or implement. Rust belt owners practically never wear engines out with normal maintenance. Sun belt owners go through multiple engines before they toss a vehicle.

The OP was/is a sun belt person with a ranch operation. So he's looking for maximum longevity, as in decades of operation. So we are parsing minutia and having a discussion on minimizing wear to some more extreme scenario while ginning up a sensible maintenance strategy

If I were the OP, I'd prolly put by-pass filters on most of the bigger stuff and change oil every 500 hours of operation. Filters would be premium and so would the TP. Filters would get changed at 250 hours and a UOA done. I'd use good oil. There would be top-ups, so the TBN/TAN ration would remain reasonable. And I'd spend my time more worried about air filtration.