What happens if you mix straight weight with multigrade?

Depending on your engine, you are able to run a 100 Miles without oil top-up. You personally will never experience a quart low.

But you are right, it is better to use some oil, no matter what oil. However, depending on your Viscoity modifier and the pour point depressant in your oil, you might end up with a 15W-40. Never theless, a straight 40 oil will never give you the wear protection of a formulated oil.

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Originally posted by Callisa:
Never theless, a straight 40 oil will never give you the wear protection of a formulated oil.

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Now that is interesting. Why? The viscosity index improvers don't lubricate, so I would think, apart from cold weather starts, the straight weight would be better.

All I know is that straight lubricants are, let's say, are rather old fashioned. At least the straight oils I know in Germany are what they claim on the package: Mineral SAE 40 oil, they are not additivated at all. They have a little wear protection due to their natural Sulfur content.
No TBN, no Dispersants, no Zinc - nothing.

Is that different in the US?

A non additive oil in USA would be rated SA or SB. I see these in straight weight and multigrade, often at gas stations and dollar type stores. Maybe OK for a fogger car (oil burner), but usually the SL rated additized oil is also present. I confess I actually did put the quart of straight 40 in my crankcase (6 qt capacity) as a sort of "experiment." I used NAPA which is Valvoline Super HPO oil (per NAPAs MSDS link from their website). It is rated SL so no problem. But next to it on the shelf was some SA or SB straight 30 oil too. Have to know what you are looking for.

Oh yeah, the "experiment." Well, I put in Citgo Superguard 10w40 SL oil (around 14 cSt) but did not get as good of oil pressure as with the Valvoline SJ Durablend 15w40 I was running (also around 14 cSt listed). Maybe is second run as I bought the Citgo at the dollar type store at 50 cents a quart, but am using it for the Auto Rx treatment/rinse phases. So maybe the Auto Rx treatment is affecting oil pressure. Anyway, the straight weight seems to have boosted oil pressure but not much and I really need to drive it more to be sure.

It appears though that one could create their own passenger car 15w40 this way as nearly all 15w40s in USA are heavy duty diesel or diesel/gasoline fleet duty with extra additives that I am concluding are not needed by me.

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It appears though that one could create their own passenger car 15w40 this way as nearly all 15w40s in USA are heavy duty diesel or diesel/gasoline fleet duty with extra additives that I am concluding are not needed by me.

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So, what is the intention of your experiment? Build your own Engine oil? Please use that oil for 3000 Miles in the winter time. Do some severe cold starts followed by some fierce high rew high load driving.

Then let's talk about Fe and Pb numbers from your engine, when you rinsed it with some RX cleaner, OK? I mean the numbers that you will find in your used cleaner, of course...

Intention of the "experiment" (not a real experiment as that would entail much work, time, money, statistics, etc) is to see what happens if I mix the straight into multigrade.

Oh no, not to run such a concoction in the winter. No telling what its cold properties are, but I have no reservation about some redline runs once it is warmed up.

Fe and Pb numbers after an AUTO Rx treatment or rinse cycle probably not to look very good. The used cleaner likely will be full of engine deposits which I would assume include some of the Fe and Pb from historical use and would be expected to be high. But to me a look at Pb and Fe well after completion of AutoRx treatment would be worthwhile.

TallPaul
This is not suitable for mixing!
http://www.motul.co.jp/eg/product_line_up/4stroke/4stroke04.html

Comment from Martin re mixing

Officially, motor oils are highly regulated to allow for compatability (this is historical in the days when motorists would be unable to get same brands in different places), so I don't think there would be a problem mixing necessarily. However, the compatability allowance may not address the performance aspect so the way in which an additive works may be affected but not necessarily cause problems so it could reduce the overall capability of the package. However, whilst I prefer to see scientific evidence of compatability on a multi-parameter test, and I doubt Redline would commit to something without testing, why not just use Mobil 1 or similar that is designed for a level of performance attempting to be achieved here by mixing?

One certainly is taking a risk when mixing oils. However, certain mixes should be harmless, such as two different viscosity grades of the same company. When I mixed 4 quarts of Maxlife 5w30 with two quarts Maxlife 20w50 I got approximately (or roughly) a 10w40. Sure, the Maxlife 10w40 likely is better, but it too will have a mix of two or more widely different viscosity base oils (See thread "Will the Real Base Oil Please Stand Up" at the Oil Guy site).

Even safer would be to mix 10w30 and 10w40 of the same brand to get a thicker 10w30 (or thinner 10w40).

My mixing straight 40 into 10w40 (albeit different brands) merely adds some variety of base oil viscosities (and/or some repeats), thickening up the base oil average viscosity and reducing the amount of viscosity index improver. As a result, probably a 15w40 or a thick 10w40.

But some specialty oils may not be good to mix. Perhaps not Motul. Redline tech person says it should not be a problem mixing other oils with Redline.

I should add that Martin's statement makes a whole lot of sense and I think it is right on.

TallPaul,

In view of grey sludge post on BITOG I would be careful about cross mixing.

However Motul allow mixing some of their oils for viscosity and should be OK for M1

Just out of curiousity: what's BITOG? Another forum?

I think it's the following forum.

BITOG = BOBISTHEOILGUY Bob Is The Oil Guy

Forum BITOG

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Originally posted by MGBV8:
In view of grey sludge post on BITOG I would be careful about cross mixing.

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Good point. Did you see, however, that MolaKule bought the same two oils, mixed them a couple weeks ago and has not had any problem with it.

Also, With Redline, I will assum about 60-70 percent ester, so I am looking at only adding about 1.5 to 2 ounces per quart. At that rate you could have run straight Redline, changed the oil to say Penzoil, and would have had 8 or 10 ounces of Redline left in the engine as it all does not drain out. I think on that low level the risk is largely mitigated, but that the ester properties will provide a significant improvement in the oil. My guess, maybe wrong.

Or one could add Rislone Upgrade which is a synthetic base oil in a 15 ounce bottle and includes about 3 oz ester. This is made to be added to any oil and should not be a problem, but at $5 a bottle (including shipping for a 6 bottle pack) it is rather expensive way to get ester vs Redline at 25 cents an ounce.

TallPaul,
A bit of an assumption will not drain - extreme view you could never change an ester oil!

The attraction must be very weak but sufficent at molecularlevel.

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Originally posted by MGBV8:
A bit of an assumption will not drain - extreme view you could never change an ester oil!

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I was actually thinking of the oil left in the lifters and some of the galleries where it does not drain off, maybe some in the pan if not all angled towards the drain plug.

Thank you. I know BITOG...the abrev. just didn't ring a bell...now it does.

TallPaul,

This would be a mix of both oils with perhaps a very thin film of ester on the surfaces IMO.

I reckon 10-20% ester which would support "Start Up" Cost, however, If Redline is 50% ester then you would need to add 20-40% Redline to mix.

Maybe M1 already has 10% ester in mix

Whats cost of Motul 8100 in US?

From a recent thread on BITOG:

Me: What level [of ester] is required to get start up protection? Would that pretty much be inseparable from the friction reduction effect?

MolaKule: A minimum of 7% for friction reduction. Startup wear is reduced by AW additives like ZDDP, Moly, or high calcium levels or medium boron levels. An oil that will flow well at startup would provide hydrodynamic lubrication, but if the oil film is thin, the AW adds would supplant those requirements.

Me: So the whole business of "Start Up" protection from polarized (ester) oil molecules is more or less marketing smoke and mirrors.

MolaKule: You got it! Now esters do provide lower temperature protection and better flow, along with friction reduction, but you need about 20% or more to really show a significant difference.

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Originally posted by MGBV8:
Whats cost of Motul 8100 in US?

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Overhere you will be able to find some Motul prices in Canadian Dollars. totalautosport

TallPaul

Due to their structure, ester molecules are “polar”; they stick to metal surfaces using electrostatic forces. This means that a protective layer is there at all times, even during that crucial start-up period. This helps to protect cams, gears, piston rings and valve train components, where lubrication is “boundary” rather than “hydrodynamic”, i.e. a very thin non-pressure fed film has to hold the surface apart. Even crank bearings benefit at starts, stops or when extreme shock loads upset the “hydrodynamic” film. (Are you listening, all you rally drivers and off road fanatics?)

Qoute from Molakule
I think a lot depends on which component in the engine you're discussing. For journal bearings, my theory is that the lubrication regime is 95% or better hydrodynamic. For cams and followers that are highly loaded with stiff springs, I suspect more boundary lubrication than hydrodynamic, say 60/40; for piston rings on cylinder walls, I would say maybe 40/60.

Another question with AW is what are the operating temperature range.

There is a lot of hype with oil - a few threads on is there a bad oil and engine damage from oil.

The jury is still out on Magnatec because its not for performance engines and is relying on start up protection

It gets quite confusing. I will stick with what Redline said to me (to freely interpret), that any amount of ester is beneficial, the more the better to the point of 100% Redline oil.

Thanks