Recent Topics
Do you have your home HVAC system maintained?
by E150GT - 06/03/20 09:21 AM
Mixing vavoline & mobil
by ThePCMasterRace - 06/03/20 09:03 AM
Pre-Oiler?
by AJB0009 - 06/03/20 09:02 AM
1992 Acura NSX, Red Line 10W-30, ~1400 miles/1 year
by robertcope - 06/03/20 06:37 AM
Rural telephone boxes along road
by dlundblad - 06/03/20 05:06 AM
Mobil1 12 quart $30 at Walmart
by wkcars - 06/03/20 12:58 AM
"The Bright Knight"
by GumbyJarvis - 06/03/20 12:35 AM
Pennzoil Axle oil with LSA.
by Snagglefoot - 06/02/20 10:03 PM
Replaced the plugs on the bike: HUGE improvement!
by 14Accent - 06/02/20 09:26 PM
Accord Trans Case crack (bad casting?)
by redhat - 06/02/20 08:38 PM
Replacement SLA Battery for Clore Jumper
by SubLGT - 06/02/20 08:34 PM
ABS codes
by 2010Civic - 06/02/20 08:02 PM
Tie rod ends - which manufactures ok?
by jdw1222 - 06/02/20 07:40 PM
Who makes their own seltzer water?
by JLawrence08648 - 06/02/20 07:23 PM
Slight Tire Bulge
by coopns - 06/02/20 06:13 PM
gm 6.2l cylinder 8 misfiring only at idle
by apollo18 - 06/02/20 04:59 PM
Ford flex
by Micahmcmeen - 06/02/20 03:42 PM
Newest Members
boathead, Digital_Dad, RobertChapmant, NewMex, RandyN11049
71596 Registered Users
Who's Online Now
90 registered members (Bluebullet, azjake, BlueOvalFitter, Blkstanger, 2015_PSD, 87sammy, 7 invisible), 1,848 guests, and 68 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics306,086
Posts5,287,120
Members71,596
Most Online4,538
Jan 20th, 2020
Donate to BITOG
Print Thread
Hop To
Page 1 of 2 1 2
Is more really better? #5430331 05/15/20 11:50 PM
Joined: Sep 2019
Posts: 64
T
TrainingPolicy Offline OP
OP Offline
T
Joined: Sep 2019
Posts: 64
Recently, I keep reading more and more threads and people are saying that “since the car takes 8 quarts of oil, I run it longer” or how ever many quarts it takes, if it takes more than 5 quarts. Yet, I never hear people saying that if a car takes less than 5 quarts they run it shorter. For example a 2005 corolla take 4 quarts of oil, and I know plenty other cars are similar as well, yet the OCI is never decreased simply due to the oil capacity. Is this idea based in any science or is it simply, ‘it has more so I can use it longer’ mentality? TIA!


2003 Infiniti G35 6MT 104k
2005 Honda Accord 235k
2010 Hyundai Santa Fe 110k
Re: Is more really better? [Re: TrainingPolicy] #5430338 05/16/20 12:19 AM
Joined: Feb 2015
Posts: 3,326
K
Kamele0N Online Sick
Online Sick
K
Joined: Feb 2015
Posts: 3,326
Oil capacity corelates also with how thermaly "loaded" one engine is....

Look on amount of oil also as it would be its cooling media...

Lets say that you have the same engine block with different outputs...

1.8 N/A....it holds 4quarts of oil...

1.8 N/A with different camshafts and therefore higher HP output....4.5 quarts

1.8 TFSi....with even more HP.... 5.5 quarts of oil + an oil cooler

Etc...





2008 Toyota Yaris 1ND-TV 1.4 D4-D Tech9 (Shell?) 5W30 C3 VW 504/507
1997 Toyota Landcruiser KZJ95 3.0 TD Shell Rimula R6M 10W-40
Re: Is more really better? [Re: TrainingPolicy] #5430354 05/16/20 02:08 AM
Joined: Sep 2010
Posts: 12,851
4WD Offline
Offline
Joined: Sep 2010
Posts: 12,851
Higher capacity can offset fuel dilution …
… my 2010 5.3L was not direct injection (DI) …6 quarts … my 2018 5.3L is DI …8 quarts

Last edited by 4WD; 05/16/20 02:28 AM.
Re: Is more really better? [Re: Kamele0N] #5430356 05/16/20 02:11 AM
Joined: Feb 2009
Posts: 17,951
D
daves87rs Offline
Offline
D
Joined: Feb 2009
Posts: 17,951
Originally Posted by Kamele0N
Oil capacity corelates also with how thermaly "loaded" one engine is....

Look on amount of oil also as it would be its cooling media...

Lets say that you have the same engine block with different outputs...

1.8 N/A....it holds 4quarts of oil...

1.8 N/A with different camshafts and therefore higher HP output....4.5 quarts

1.8 TFSi....with even more HP.... 5.5 quarts of oil + an oil cooler

Etc...





Yep, depends on many factors......


2020 Chevrolet Trax LS
2019 Chevrolet Equinox LS
2006 Chevrolet Cobalt LS
2004 Chevrolet Cavalier (project)

Re: Is more really better? [Re: TrainingPolicy] #5430361 05/16/20 02:24 AM
Joined: Jul 2010
Posts: 23,686
Z
ZeeOSix Offline
Offline
Z
Joined: Jul 2010
Posts: 23,686
The recommended oil change interval the engineers put in the owner's manual should reflect the sump capacity to some degree.

Re: Is more really better? [Re: TrainingPolicy] #5430382 05/16/20 04:59 AM
Joined: Apr 2020
Posts: 407
ABN_CBT_ENGR Offline
Offline
Joined: Apr 2020
Posts: 407
Originally Posted by TrainingPolicy
yet the OCI is never decreased simply due to the oil capacity. Is this idea based in any science or is it simply, ‘it has more so I can use it longer’ mentality? TIA!


The correct answer is the majority of people making these statements are basically using the "3 blind men describing an elephant" method of anecdotal engineering.

Sump engineering ( wet or dry) is a science unto itself and those outside of machine design probably don't even know it exists. (I know I didn't when I started and I was brought up to believe many of the things currently stated about sumps and levels and had to change my whole way of evaluating them)

In a very short tutorial ( and hardly comprehensive) the sump level ( dipstick) is DECOUPLED from the lubrication level ( defined as the lubrication necessary to lubricate the machine)- that's a distinction with a difference as will be seen.

So you start with the volume of "active lubrication" with a thermal load and come up with a cooling cycle- that's your baseline.

Then consider the delivery system ( pump, splash etc)

That gives you a basic volume then you need to cool it ( determines the physical properties of the sump as below the thermal zone, thinner metal for thermal transfer, air flow etc)- You really cant overfill a sump that is decoupled from the active or thermal zone of the machine. This is why some gearboxes and couplings have different fill levels and volumes for different orientations.

Then you have the pick ups and levels relative to tilt, orientation, sloshing and so forth.

That's basically the universal fundamental method then everything beyond that goes application specific and that's a whole different level and type of considerations and often has a lot of T&E built in.

On the change part- the forces acting against the oil determine its service life and depending on what specific quality of the oil in question- volume can play a part in the interval and in some situations it doesn't.

So there is a science to it but its not an absolute and it has a lot of things to consider.

Re: Is more really better? [Re: TrainingPolicy] #5430408 05/16/20 06:41 AM
Joined: Sep 2004
Posts: 24,373
Mr Nice Offline
Offline
Joined: Sep 2004
Posts: 24,373
More oil = longer oil change intervals.

Re: Is more really better? [Re: TrainingPolicy] #5430411 05/16/20 06:42 AM
Joined: Jun 2003
Posts: 35,652
E
eljefino Offline
Offline
E
Joined: Jun 2003
Posts: 35,652
"They" say to change oil after a certain amount of fuel has run through. They use this for oil-life-monitors. More cold starts, more idling, more city traffic means more fuel burned per mile, and a shorter OCI.

A corolla is good on gas and burns less fuel, so it fatigues its oil more slowly. There's less of it, so we see a normal-ish change interval.

(The flip argument is a tiny engine is wound up more of the time, and would shear it down faster.)

I also think some engineers know the American market, and how Jiffy Lube gives everyone 5 quarts for the normal price, and oversizes their sump capacities to take those 5 quarts as a buffer against running long, or running low.

Re: Is more really better? [Re: TrainingPolicy] #5430441 05/16/20 07:46 AM
Joined: Aug 2013
Posts: 3,980
H
HangFire Offline
Offline
H
Joined: Aug 2013
Posts: 3,980
If it's a wet sump engine (vast majority of automotive engines), it's not entirely decoupled from the engine lubrication, is it?

There is a general correlation between factory vehicles with very long OCI's, and the size of their sumps. But there are also similar correlations between turbo engines and their sump size, and performance engines, except a few where there is not.

My 1.8L Corolla takes half a quart more oil than my 3.9L V6 Dakota. Make of that what you will.


Various musings: http://hangfire.net
Re: Is more really better? [Re: TrainingPolicy] #5430443 05/16/20 07:49 AM
Joined: Nov 2008
Posts: 16,040
S
supton Online Content
Online Content
S
Joined: Nov 2008
Posts: 16,040
I sorta do that. I have vehicles with 4, 5 and 8 quart sumps. The 8 quart sump is lightly loaded--heavy truck that is barely used and has an oil cooler. The 5 quart vehicle sees "typical" usage and gets 5k in winter, 10k in summer. The 4 quart sump one has no engine oil cooler and has to live under my right foot--if it wasn't for it using a quart over 3 or so k I'd probably change all the sooner.

IMO the OEM's tend to take this all into account. A 3 or 4 quart sump was deemed sufficient for typical by the OEM for whatever duration they wrote down. We at BITOG like to overthink things, and I enjoy my little world of FUD. But you have to admit, the smaller the sump the cheaper it is to change.


2011 Toyota Camry, base, 2.5L/6MT, 205k, hers
2010 Toyota Tundra DC, 4.6L/6AT, 159k, ours
1999 Toyota Camry LE, 2.2L/4AT, 225k, his
Re: Is more really better? [Re: HangFire] #5430465 05/16/20 08:11 AM
Joined: Apr 2020
Posts: 407
ABN_CBT_ENGR Offline
Offline
Joined: Apr 2020
Posts: 407
Originally Posted by HangFire
If it's a wet sump engine (vast majority of automotive engines), it's not entirely decoupled from the engine lubrication, is it?

There is a general correlation between factory vehicles with very long OCI's, and the size of their sumps.


No its not but it is ( let me explain because its literally up to the individual design team and what they considered important and what they didn't)

X+Y= 7- At this level there is an infinite ability to relatively define X & Y- that's how sump calcs go. This is basically the same info in the ML-1 &2 sump training and this subject comes up often.

At any level there is a "correlation" between volume and lifecycle of a lubricant but its hard to define based on that because each variable ( need to dissipate heat, particulate contamination, chemical contamination, additive consumption and tons more) has a different effect and impact on the overall lifecycle relative to total volume available. That's not even attempting to capture end use specifics like the way you personally use the machine.

(Particularly in an ICE rather than in most industrial equipment which run usually steady state)

The designer cannot possibly capture them all or investigate every possible scenario- the only "standard" is the heat removed from the various regimes so that's what the baseline calculation is based on.

They everything else is best guessed with a good margin of error. Theres also input from lube manufacturers and inputs from various studies and all that.

Theres a lot of room built in for error, expansion and other things.

Re: Is more really better? [Re: TrainingPolicy] #5430471 05/16/20 08:19 AM
Joined: Nov 2002
Posts: 33,284
B
buster Offline
Offline
B
Joined: Nov 2002
Posts: 33,284
Ted Kublin (Tooslick), who was one of the most knowledgeable people on this site at one time came up with this formula.

OCI = (C*)(ave mpg)(sump in qts)(cubic inches/Hp)

"Where C* is a constant which was derived by looking at oil analysis data I've accumulated over the last 10 years. For Amsoil I use a C* of 120, which generates drain intervals of approx 7500 miles for a turbo or motorcycle, up to 15k-20k for a low power density engine driven easily on the highway. If you have an application where you are dirt or soot limited, you can't use this formula and get a good estimation of oil life.

You CANNOT use the TBN times ten as a substitute for this C* value. The rate of TBN depletion varies significantly depending on the quality of basestock and additive chemistry. In addition, TBN depletion is non-linear, as you have seen from the 3MP tests. In other words, a 6 TBN oil will not last 50% as long as a 12 TBN synthetic. In actual practice, it might only last 25%-33% as long.

I don't have as much data on other oils as I do with Amsoil in deriving additional C* values. For Mobil 1 I suggested using a C* of 80, based on the limited data I've seen on this site. For an average quality petroleum lube, I think a C* of 40 is reasonable. The implication of using these various C* values is easy to see ....

Please feel free to contact me off-line if you have any other questions about this OCI formula. BTW, I've made my living as a propulsion engineer for the past twenty years - the Amsoil stuff is something I do on the side."


2020 - Mazda CX-30 - Mobil 1 EP 0w20
2019 - Subaru Impreza - Dealer Oil
Re: Is more really better? [Re: TrainingPolicy] #5430475 05/16/20 08:24 AM
Joined: Aug 2018
Posts: 1,258
RDY4WAR Online Content
Online Content
Joined: Aug 2018
Posts: 1,258
I feel like the sump capacity does have an impact on service life, but not as much as the engine itself. Take 2 engines that are exactly the same except one has a 4 quart sump and the other has a 6 quart sump. The 6 quart engine can spread the same fuel dilution, water dilution, combustion by-products, soot, etc... across more oil (50% more) and therefore should result in slower TBN loss. The higher sump capacity would also mean more cooling which would slow oxidation. Though I've never done an A-B-A test of this myself, I surmise that a larger sump capacity, with all else equal, would result in a longer service life.


"He who is without oil, shall throw the first rod." - Compressions 9:1
Re: Is more really better? [Re: TrainingPolicy] #5430487 05/16/20 08:36 AM
Joined: Feb 2014
Posts: 3,918
Marco620 Offline
Offline
Joined: Feb 2014
Posts: 3,918
I follow the MM on my Honda. Granted I know this car up and down and have had various samples taken to know where the end of the oil fill is at. I have noticed that my fuel quality, air and oil filtration and willingness to check the oil level every month and top off if needed has contributed to its longevity.
As I get closer to buying a brand new civic which has a small oil sump I will consider many options to keep oil in safe operating. I'm not too worried about fuel dilution with non ethanol fuel and highway driving. Will run a 3.0 or higher hths oil and possibly a small oil cooler from GReddy or Mishimoto. Think the thinnest I'll go is redline 0w20 or blend M1 0w30 / Redline 0w30.


15' Civic r18, 335,000 mi M1 0w30/5w30 & LG Biotech,Castrol CVT Fluid,Redline Si-1
Dog Whisperer! Honda/Acura nerd; detest ethanol,wind, and anything vegan.


Re: Is more really better? [Re: TrainingPolicy] #5430498 05/16/20 08:46 AM
Joined: Oct 2014
Posts: 15,254
C
CT8 Offline
Offline
C
Joined: Oct 2014
Posts: 15,254
It depends.


2015 F150 2.7
2018 F350 6.2
Page 1 of 2 1 2
Previous Thread
Index
Next Thread

BOB IS THE OIL GUY® Powered by UBB.threads™