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It appears to me (after a 10 minute internet search) that this stuff is an SM oil, and therfore has a small dose of ZDDP (maybe 800 ppm and its a group-III oil). Castrol makes a similar oil in their race lineup with the full 1200 ppm ZDDP levels.

Note: Race oil is NOT FOR GARAGE QUEENS, its for cars that get the snot run out of them and the oil changed regularly.

 

Mitch,

285 oil temp seems a bit high. What is the allowable operating temp before you get breakdown and power loss? I know the new oils can take 400 but the motor does not like that.

 

Just because it's SM, doesn't mean it's going to be limited to 800ppm phos. That limit is only on energy conserving grades, ie. 30wt and lower. Any 50wt will almost certainly have more than that. 1000ppm+.

1200ppm isn't the 'full' phos level for a race oil. You get that amount in M1's 15W-50 street oil. Even the 0W-40 has 1000ppm. M1 race oils have 1750ppm phos.

Fatbillybob, I imagine the hardware material, age, etc all play into it, but I know of a NASA Honda Challenge engine that eventually was destroyed as a result of high oil temps. It started out that it would backfire/shoot a flame on downshifts when the oil temp was above 280F and get worse as that went higher. This was a sign that a valvespring was hanging in those downshifts. One eventually failed, dropped a valve and took out the motor. This was an engine that was using the factory oil-water heat exchanger. And revving to 8500+, a lot of heat is generated in the valvesprings. Then again, there are turbo-Honda engines that go past 300F, but don't rev quite as high and don't have problems. So it depends..

Spending a few hundred $$ on a Mocal cooler to bring temps below 250 is a wise investment imo. Oil also wears tremendously more at the higher temps.

 

Simply going by the original factory oil (Shell UH 10W-40 with an HTHS of 4.2 at 305dF) and a factory set oil redline at 305dF; I have been running on the assumption that 305dF is where the wear starts to rise rapidly--rapidly enough that the manufacture was willing to set the red line at this point. Now, my car never sees the high side of 285 at 103dF ambients on race tracks with the throttle pinned much of the time, and is often at 185dF in street driving.

The temperature at which one should quit getting it on and start saving the engine is dependent on the viscosity of the oil (especially the HTHS number). Since the factory gauge is set at 305dF and HTHS of SHU is 4.2 cP at 305dF I suspect that the real criterion is that the oil always display an HTHS equivalence above 4.2 cP. So, for example, RedLine has a 10W-30 oil with an HTHS of 3.8 cP at 305dF. I have used this oil in my F355 in track conditions at 102dF ambients. I kept an eye on the oil temp gauge and the oil did not get above 285df--because at 285dF this oil has an 'eqivalent' HTHS of 4.2 cP (just not at 305dF). Equivalent is in quotes because HTHS is only measured at 305dF but if the same procedure was used at 285dF it would measure 4.2 cP. Oil pressures on track wer just fine, idle oil pressures comming off the track after a cool down lap were 'a hair low' but still above 10PSI/1000RPMs.

Still I recommend xxW-50 oils for track use where the driver can not or will not look at the temperature gauge and save the car when danger presents itself. Even with my best efforts in high performance back road driving, I can't get the oil temps above 260dF; so I see no reason why anyone would need more than xxW-40 oil unless race track use is envisionied (older cars excepted). If my car were to never see the track again (or not durring that oil change interval), I would convert it to 10W-30 oil.

I do agree with the notion that the synthetics oils can take more heat than can the engine itself. probably 450-500dF before any molecular damage occurs (in a frying pan for example). In an engine, we don't so much care about the saving the oil as in saving the engine (parts).

 

Hi Mike,

I sent a request for info about suitability of redline oils, possibly with additional zddp and received the following response:

Chris,


Thank you for contacting Red Line Oil, in your 308 I would recommend the 10W40, I would expect the pressure you are experiencing is sufficient and you shouldn't need additional. The 15W50 or 10W50 would be options, though shouldn't be necessary. Our motor oils all contain 1200 ppm phosphorus, sufficient for your cams and followers, additional ZDDP wouldn't be necessary.


Regards, Dave
Red Line Oil


However, Due to the low, (50-55 psi at 255 f) oil pressure with the 5-50 syntek, i am gong to follow your lead and go with the redline 5-50, i think mitch was going for xx-50 as well).

hth,
chris

 

Hi Mitch, I heard of people recommending xxW-60 for this same reason - what do you think?

 

Ali, how quickly do oils break down? I use Castrol gtx 20/50 in several cars, and oil pressure is noticeably better the first day you use them...within 1 week, it dwindles down by 10-15psi...and then stays there. Is the oil degraded this much simply in its initial use?

 

Reducing two grades in such a short amount of "steady" mileage is very unusual. My 10W 60 (different formulation) doesn't shear thin anywhere near as much as this. Hence you can't generalise about viscosity grades. It depends on the specifics of the formulation!

 

I, personally think that it is overkill. Here is the line of reasoning::

1: Factory recommended oil has its redline set on the oil temp gauge at 305dF
2: xxW-50 oil is going to be as good at 325-330dF as the factory oil is at 305dF
by the time the oil gets to and stabilizes at 325dF,
3: the water will have reached 235dF* and the pressure will blow either the cap, a hose, a clamp, or a radiator.
xxW-60 oil (assuming it stays a -60 oil) should be good to 345-350dF,
4: you will have blown the water system way before this point (see points 2: and 3.

(*) I regularly see 225dF water temps on track, I have blown a hose clamp on track.

 

Mitch - I think you are still missing the point that we discussed around Christmas time. It's not only about what maximum temperature the lubricant is capable of operating at that's of interest, but also the degree of protection provided at any fixed temperature point (for example 305 dF). A XW 60 will provide better protection than a XW 40 (for example) at any operational temperature point (assuming an engine up to working temperatures).

You maybe have a point that it's not strictly necessary but I personally prefer to have some margin of safety when I'm driving my car hard.

 

There are many SAE papers around that indicate once the viscosity is sufficient to float the surfaces and prevent metal to metal contact, that wear essentially stops. That is, if the parts are 3 micron apart or 37 mircons apart the wear is no different: 0=0.

And then there a bazillions of SAE papers showing that thinner oils: a: have less startup wear, b: have less ring and cyclinder wear, c: allow engines to live longer lives,.....

No, Haith, you can't seem to put together a cogent argument other than the hand waving thicker is better thingie. While me, the non-tribologist, can put together well composed thought trains that make sense. And I have the lack of wear data to at least demonstrate that my side of the argument has done no harm under the worst possible conditions of use. So, what is it that makes one 4.2 cP oil at temp 'A' better than another 4.2cP oil at temp 'B'? If (the BIG if) you are a usefully decent tribologist, you COULD answer the question, but given 3 chances you have simply declined. Not much of a tribologist are you?

Now, most of the time, me driving around ow 10W-40 oil at 185dF (interstate and back raod cruising) my viscosity is MANY times what is necessary for absolute maximum protection (around 20 cP, while wear does not begin until around 5 cP). The only time it is even somewhat less than this is when I run the snot out of it and the oil temp gets into the 280dF range.

 

I believe that only applies to extreme temps. A 15W50 weight synthetic has an excellent pour rate until you're talking about arctic conditions.

As I understand it, the W rating of multi oils is a scale of how old mineral oils maintained at low temps. Today's heavy weight synthetics don't gel up nearly as bad, and the winter rating is of less consequence with full synthetics.

I have read the majority of engine wear occurs at start up. I like Motul 300V which is polar and sticks to the metal, instead of draining completely off the bearings etc.
Looking at the product line, they recommend the thicker oil for reliablity and the thinner stuff for pure performance. http://i47.tinypic.com/1zmp40h.jpg

 

I am amazed by the degree of arragance shown by your posting. I'm interested to know what you do for a living that puts you in a position of such confidence concerning your comments. Its only a week ago that you were telling everyone on this forum that multi-grade synthetic oils don't contain viscosity modifiers - that's a joke, together with the majority of your other mis-informed knowledge! How can anyone take anything you comment on seriously after comments like this?!

Just for the benfit of other less cocky "know it alls" reading this thread, I will cover your points below:

MITCH ALSUP: "There are many SAE papers around that indicate once the viscosity is sufficient to float the surfaces and prevent metal to metal contact, that wear essentially stops. That is, if the parts are 3 micron apart or 37 mircons apart the wear is no different: 0=0."

You don't need to read SAE papers to know this - a little bit of common sense will do. However as I'm a tribologist and you aren't, I can tell you that there is a difference in wear / durability because you have failed to consider the composite surface roughness of the parts you are lubricating. If the composite surface roughness is 4 um and the oil film thickness is 3 - you still have wear and are still in boundary / mixed lubrication. So - ANOTHER MIS-INFORMED POINT.

MITCH ALSUP: "And then there a bazillions of SAE papers showing that thinner oils: a: have less startup wear, b: have less ring and cyclinder wear, c: allow engines to live longer lives,....."

a) yes I agree. b) please send me references statistically demonstrating lower ring / liner wear with a low viscosity oil compared to a higher viscosity oil using the same formulation chemistry and base oil type. c) see my comments for b.

MITCH ALSUP: "No, Haith, you can't seem to put together a cogent argument other than the hand waving thicker is better thingie. While me, the non-tribologist, can put together well composed thought trains that make sense. And I have the lack of wear data to at least demonstrate that my side of the argument has done no harm under the worst possible conditions of use."

Few of your arguments makes any sense to the well informed in this area, because you simplify every one of your assumptions (this tends to happen when you don't know as much as you think you do!). Whilst I am happy to advise others who ask for help and also contribute to the content of this forum, I will not tolerate arrogant amateurs questioning my abilities as a professional engineer with the attitute you take - hence this will be my last communication with you.

MITCH ALSUP: "So, what is it that makes one 4.2 cP oil at temp 'A' better than another 4.2cP oil at temp 'B'? If (the BIG if) you are a usefully decent tribologist, you COULD answer the question, but given 3 chances you have simply declined. Not much of a tribologist are you?"

This question is nonesense. Why are you asking me to compare two oils with the same HTHS at different temperatures? This question has no relevance to the discussion we are having because a 10W 60 oil would typically have a HTHS much higher than your lower viscosity oil! Hence when the 10W 60 oil enters the high temperature, high shear conditions of a bearing or ring / liner contact it will have a higher OFT (oil film thickness) than any of the lower visocsity oils you keep telling us are so good. Hence under high load conditions my 10W 60 is likely operating under EHL conditions in the valvetrain (your much lower viscosity is probably under boundary conditions and therefore wearing your engine). Similar arguments in the bearings and ring / liner contact - lower visocosity entering boundary lubrication at TDC, 10W 60 still likely to be in mixed.

MITCH ALSUP: "Now, most of the time, me driving around ow 10W-40 oil at 185dF (interstate and back raod cruising) my viscosity is MANY times what is necessary for absolute maximum protection (around 20 cP, while wear does not begin until around 5 cP). The only time it is even somewhat less than this is when I run the snot out of it and the oil temp gets into the 280dF range."

If you were correct then none of the engines in road cars would ever wear would they? You howerver tell us that all contacts in your engine are operating under hydrodynamic lubrication because "my viscosity is MANY times what is necessary for absolute protection". What a load of c***!

Where have you got those numbers from you are quoting? Two comments:

1) a 10W 40 will not have a kv100 of 20 cSt! That is a XXW - 50
2) You may want to check your units. You are quoting dynamic viscosity units for a kinematic viscosity. This tells me you don't understand the difference between kinematic visocsity and dynamic viscosity!

So in conclusion another useless statement from you riddled with inaccuracy.

THE END.

Caution to other forum members: We have another example here of someone who goes around giving others advice believing he knows it all. You will see from the above post that the questions he asks make no sense and most statements are full of errors.

 

In conclusion, you still can't answer a simply question about how two oils in an engine operating at the same actual viscosity deliver different levels of protection to that engine.

 

The problem is Mitch that although your argument sounds like logic, it isn't. Your argument relies entirely on the incorrect assumption that the temp you see on your gauge tells you something about the maximum oil temp....it simply doesn't. It tells you the AVERAGE temp whicvh is not particularly helpful for making changes to the oil system. After the temp data is out you have nothing left other than luck that nothing bad happened when you did it. What you have is a dangerous argument based on pseudoscience that directly contradicts the recommendations of all the major performance vehicle manufactures….the people with reams of actual test data and the people who need to warranty the engines.

 

Couldn't agree more.

 

Am I detecting a note of hostility in the above note? I dare say yes.

I understand that a therapeutic approach utililzing anger management as its primary core works wonders.

If that doesn't work, there is always that last option. Yes, the pill.

Ciao,
George
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Hello,
I'm new and I’m bringing an old thread up. I don't have a Ferrari, but I have several BMW, 550 and M3 and I wonder about oil a lot and read a lot as well. BMW is recommended A3/B3 oil (not sure how this is different than A1/B1 and ect oils), and very high viscosity at 100 C , it's all above 12.1 at least. So after reading this long and good written thread, I noticed it's not mentioned anything about HTHS numbers, even there so close like xW-20 ~ 2.6 and xW-30 ~ 2.9, but does it most important number for long last engine?
Also a lot cars are using advance system for valve train, like Vanos, and it's base on oil pressure, so low viscosity oil has lower pressure, and it can effect this system, don't you think ?

Thank you

 

I may / will probably get hammered for this but...

I use LUCAS oil additive in my motor because it specifically states it keeps the pistons coated
to reduce friction,

Any intelligent comments ??? I am really curious if this is a good or bad thing?

I also use the LUCAS additive for my fuel.

Thanks to all who may respond!

 

Good question, I use the oil additive and gas additive in my Hummer H2, but have hesitated so far in my 430. Input appreciated.

 

Brilliantly written. Thank you for your diligence on this very old but important topic!!

 

Hi Doc.I am using SAE 20W-50 LIQUI-MOLY mineral oil touring high tech in my 1988/328 85k miles no winter driving no tracking changing every spring and no oil burn at all.is this oil good for high mileage cars.