Help with SAE viscosity numbers.

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Originally Posted By: Dad2leia
Originally Posted By: Oilgal
Thanks Gary. But I would rather drink 5w-20 than get 'nipped & tucked'.
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Now why wouldn't you want to get "nipped/tucked"? I thought that was every woman's fantasy operation, but couldn't afford.
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Yes, that is the media stereotype alright, and yet many of us have seen what it has done to our friends, in the long run.

I really 'do' like what 5w-20 is doing for my engine though. Man o man is it ever quiet now.
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Gary, maybe your wife is so sensitive about her car, because she knows how much you care about lubrication and maintenance. That may be her way of being in simpatico.
 
widman

I wanted a 63 Corvair convertable so bad it hurt. I wound up buying a brand new 64 Buick convertable. It cost me $2,400.00 to get it out the door. My Dad bought a Corvair van!!!

I read you paper about a week or so ago. Actually it was your paper that got me to start rethinking and to post here.

AEHaas

Thanks for the link. That was very helpful and makes sense.

For the both of you, how do you determine the best oil from what is available to us today. I was looking at the specs of two highly spoken of oils here, I won't mention brand names, just data sheet info. Both oils are 5w30 synthetic.
Oil A
100C= 11.3
40C= 64.8
VI= 169
POUR PT= -48
HTHS= 3.09
TBN= 11.3

Oil B
100C= 10.7
40c= 59
VI= 174
POUR PT= -50
HTHS= 3.2
TBN= 12.2
I would pick oil A because of the 100C viscosity of 11.3, which to me means better protection. Of those two which is the best oil, and why, or is there no real world difference?

Thanks for all the help and responses from everyone.
 
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There is no evidence in todays oil research that suggests the thicker oil is any better in any way. Higher viscosity means lower BHP and less MPG and has no effect on wear.

I would pick the one that is less viscous at room temperature and with a lower pour point and with a higher VI. HTHS, viscosity at 100C and TBN are over rated and throw people off more important chemical values. I am more concerned with TAN in used oil analysis and retention of viscosity. The effects of fuel dilution on oil properties are very important to those who do not live only on the highway.

To mention just a few things.

aehaas
 
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I do move in progression despite what seems as radical oil type changes to some people. For example I went from the OEM 5W40 Agip to 0W30 Mobil 1 in Linda's Murcielago. I then went to 5W20 Red Line, a "thick" 20 grade oil. Now we have the RLI 0W20, an average 20 grade oil. By the sound of it (the engine) I am not concerned about wear. I will do an oil analysis and see what I get.

In the Enzo I saw that the OEM oil went from a 60 grade to a 40 grade in 1,000 miles so I tried a "thick" 30 grade, the Castrol European Formula "GC". It gave less than half the wear of the OEM oil in the same conditions. Now I am running the olive oil, thin, 0W30 RLI. Again, I am confident it will show even less wear.

I have no problem with Castrol GTX 5W20.

These engines / cars I am testing are new and oils are frequently changed. There is no build up or sludge to cloud the oil analysis. For the most part what you see is what you get. My results are discussed among the importers and several people within the industry. I am not worried.

For my applications oil related wear is at an absolute minimum. BHP and fuel economy are at absolute maximums for these vehicles.

aehaas
 
Thank you Dr. Haas.

I have been using that very oil, in my old Mitsu 3.0, for about a week now, and it runs quieter than it ever has. My mpg have increased by about two also. As well, my oil consumption has reduced to apparent zero, and the throttle response and acceleration is amazing!

Thanks for turning us to on lighter weight oils.
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Yes, Dr. Haas, viscosity is the falsely bashed poster boy of oil demons. If you can keep the bearings apart ..then it's down to your add pack to manage the rubbing components. Beyond that, you're down to TAN/TBN/OX/NIT/Flash/Fuel%/etc...

I do fancy heavier HDEO synthetics ..but just don't have much of a use for them.
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Amsoil HDD will probably end up being my oil of choice after the next round or two with Bruceblend® 0w oils.
 
Frank, I can understand what has worked for you in the past. Back 20-25 years ago, the only oil I would put in my air-cooled equipment and engines was Mobil 1 15W-50, esp. for heavy summer use. I was not able to wear an engine out with that oil in it. Todays's conventional oils just run much cleaner and the gap between synthetics and conventional oils has really narrowed considerably due to better basestocks and additives. Even engines have changed overall with lower friction/wear valvetrains and in some cases better materials/design and manufacturing. I still favor synthetics, but only when run long enough to warrant using them. For the under-5000 mile oil changes you are talking about, synthetic oil would be a waste IMO since regular oils are now keeping wear and deposits in check at those intervals. Most synthetics can go 6000-7500 miles and some, even syn blends can go much longer depending on application and use. Europe has been doing 10k mile oil changes for a while now, but we seem to be stuck somewhere between 4-5k miles overall.

I would have to say my favorite retail 5W/10W-30 or 5W-20 synthetic is Pennzoil Platinum. Best value 5W-40 retail oil is Rotella synthetic (known as RTS around here). These are all capable of extended drain intervals and low wear.

Big fan of Schaeffers products, too. Schaeffers makes a great syn-blend 5w30 and full syn 5w30. Their 5W-40 is really stout (heavy duty), but probably overkill for new passenger car service, but a diesel...well, it's my favorite.

Amsoil has several 5w30's for different applications/service duty and drain intervals. All are excellent in my experience.
Their 5W-40 is aimed at Euro cars due to chemical limits of certain specs and HTHS minimums, etc. but its higher viscosity is not really needed in most cars without a turbocharger. It's on the thinner end of 40 weight where the HD diesel 5W-40's are a bit heavier.
 
What about friction modifiers. Are they to make the oil more slipery as a lubrication aid or are they to make the oil easier to pump through the engine?

I know that motorcycle oils do not have friction modifiers becuse they are bad for the wet clutches. That would make me think they make the oils more slippery as a lubrication function.

I also read on a post here, somewhere, that I cannot find now, that diesel oils do not have friction modifiers yet I was considering a 5w30 diesel oil for use in my gasoline truck engine. Why would a diesel oil not have friction modifiers? What would be the effect of using an oil without friction modifiers?
 
I'm about to pull the trigger on one of the Amsoil 5W40's for my turbo, but the price of gas has me thinking of running SSO 0W30.

I'm also a bit leery of thin oils since I'll occasionally tow (small utility trailer or possibly Uhaul) and it gets close to 100F in NJ. Subaru allows 5w30, 10w30, 10W40 and more!

Frank,

Some of the benefits of friction modifiers are less drag and improved fuel economy.

Doc Haas,

Do any of your cars have turbos?

-Dennis
 
"Do any of your cars have turbos?"

'Only the Maybach 75s and the Bentley GTC. The OEM Bentley and Maybach oils are both 30 grade. 40 grade oils are spec'ed. I have not changed the Bentley oil yet but the Maybach, including the previous plain 57, all run - ran with Red Line 5W20. The UOA so far have been excellent.

Both cars will get 0W20 RLI at some point.

aehaas
 
Originally Posted By: Oilgal
Gary, maybe your wife is so sensitive about her car, because she knows how much you care about lubrication and maintenance. That may be her way of being in simpatico.


She has no trouble finding "Honey-Do" stuff for me. I've often pondered that Honey-Do things are to fill the gap that women feel because men don't know how to tell their SO's that they love them. Somehow, they just can't take this for granted and continue on. Now my wife has an advanced degree in this discipline and has evolved to the level that all overtures of love must involve painful sacrifice to be "real".

..but, yes, she does feel the need to give me a purpose. After the pups are at a certain level of development, we're somewhat dead weight (as I ponder the true meanings of mating and nesting rituals
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Originally Posted By: Gary Allan
Originally Posted By: Oilgal
Gary, maybe your wife is so sensitive about her car, because she knows how much you care about lubrication and maintenance. That may be her way of being in simpatico.


She has no trouble finding "Honey-Do" stuff for me. I've often pondered that Honey-Do things are to fill the gap that women feel because men don't know how to tell their SO's that they love them. Somehow, they just can't take this for granted and continue on. Now my wife has an advanced degree in this discipline and has evolved to the level that all overtures of love must involve painful sacrifice to be "real".

..but, yes, she does feel the need to give me a purpose. After the pups are at a certain level of development, we're somewhat dead weight (as I ponder the true meanings of mating and nesting rituals
wink.gif
)



Thing is Gary. All you men, sincerely, wonderful as you all are, are just as crazy as we are in but somewhat different areas.

I have given up, trying to understand our differences and sorting the causes for them, and instead I have settled for quiet acceptance. When I need reassurance I just ask for it, and I accept the fact that I must do so.

Is this an irrational need of ours? Honestly I neither know or even care anymore. It is just the way it is. I am glad that I am so lucky, that my spouse is always happy to give me that hug and tell me how special I am, and we can laugh together about the fact that I have to ask.
 
Does anyone know what the GM 4718M spec really is as to viscosity at 40C, 100C, HTHS, pour point, etc?

It looks as if my best oil is going to be either Amsoil 3000 5w30 HDD or Amsoil ATM 10W-30. I looked at the Amsoil 5W-40 AFL but the TBN, Noack Volatility, and 4 ball wear test were not as good. I liked the Mobil 1 0W-40 spec sheet but they did not include pour point, Noack Volatility, or any wear specs. Does anyone know anything about this offering from Mobil 1?

Thank you
 
No need for synthetics if you're running less than 5K OCIs. If you're going to continue the conventional thinking process of old, stick with conventional oil as indicated by your owner's manual and assuming your 3k OCIs. But if you consult your owner's manual, you'll probably notice that 3K OCIs are a thing of the past. Do a google search for "GM oil life monitor" IIRC. There's a PDF file I've downloaded to give to my father (old school) that shows OCIs of 5-7K with conventional oil with city driving.

If Mobil 1 is your oil of choice. Consult their website and some insight to what synthetic potentially hold.
 
Originally Posted By: FrankN4
Does anyone know what the GM 4718M spec really is as to viscosity at 40C, 100C, HTHS, pour point, etc?

It looks as if my best oil is going to be either Amsoil 3000 5w30 HDD or Amsoil ATM 10W-30. I looked at the Amsoil 5W-40 AFL but the TBN, Noack Volatility, and 4 ball wear test were not as good. I liked the Mobil 1 0W-40 spec sheet but they did not include pour point, Noack Volatility, or any wear specs. Does anyone know anything about this offering from Mobil 1?

Thank you


You're looking at a very expensive oil to change out <5K! :2cents:
 
Corey

The Toyota truck is now geting about 1,500 miles a year. I change the oil twice a year. The Cavalier is now down to about 12,000 miles a year. The 2008 Silverado will get about 8,000 miles a year, but it will also be the one pulling camping equipment through the Smokey Mountains twice a year in 80 degree temperature. It will also make the two road trips to Myrtle Beach and Arlington, VA. I can change the oil in any of my vehicles with Mobil 1 and a Wix or Guard filter for $28.84. To me that is cheap peace of mind.

I am still not totally convinced that I should not use synthetic 15W-50 in the Silverado. I read that a 15W synthetic would flow at startup about the same as a 5W mineral oil. If I can verify that, I will definately use the 15W-50 in the Silverado.

I think my hangup is that I don't trust the manufacturers. I think they are more interested in their corporate average gas mileage, fuel economy, than they are in my getting 250,000-300,000 miles from my engine.

We must also consider the fact that I am just an old geezer.
 
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