Best oil? Type, brand, viscosity, additives, etc.

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AuroraGirl

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I found this on a gm techconnect or whatever article. in november dexos-3 spec oils are coming out and at that time only 5w30 and 0w20 were find-able
 

AuroraGirl

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I use a 50/50 blend. And like Curt, I use Lucas products.
The notion that synthetics are "too slick" has been disproven many times.
Today's oils, even conventional, are light years ahead of 30 - 40 years ago. Most have very good additive packages and will be fine.
Just make sure to change it regularly.
And toss the break-in oil after 100 miles, it'll be dirty.

Best things you can do while the block is at the machine shop is to have it torque plate honed, then plateau honed. Plateau honing knocks off all the microscopic peaks left by honing stones and makes 'em flat-topped, like a plateau. This cuts down break-in time significantly. While you're at it, have the block decked square. I have mine cut to leave the piston .005 in the hole.
I have one I built about 15 years ago that now has 125K miles or so on it. With flat top 4 valve relief pistons, I'm at 10.1:1 with vortec heads and an LT-4 stock cam. Oil looks brand new at 1000 miles thanks to how well the rings seal, particularly at TDC where the torque plate honing job really shines.
I think too slick is a ignorant(not in a disparaging way) but a someone explained at one point shear stability and behavior of oils... kinda a your hearts there but the game of telephone twisted the lessons etc.

Also, we all know, the best oil is 5w30 from the general itself
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Its gonna take a few bottles and probably 4 dealerships stock of it to do an oil change but you will see results quick!
 

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This is just flat out not true. 10w-30 is not "10 weight oil". 10w-30 is a 30 weight oil that has additives in it to prevent it from thickening as much at cold temperature. A 10w-30 and a straight 30 weight will have the same viscosity at 100 degrees C, because that is how the oil gets graded. If they had different viscosities at that temperature(which is right in the middle of most engines standard oil operating temp), they would not both be -30. The "10W" at the front means that the oil will have the same viscosity at cold temperatures as a SAE 10 oil would at that temp. This is still thicker than either of the oils at "operating temp". If you look at the graph below, you can see how the 30 and 40 weight oils, whether they are straight grade or multi-viscocity all converge to almost the same viscocity at operating temps. They vary widely at cold start temps though. Once you get to freezing temps, the SAE 30 has double the viscocity of the 10w-30.

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If you zoom in on the top end of the graph, you can see that the SAE 30 and 10w-30 have the exact same viscocity at normal operating temps.

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If you live anywhere that gets below freezing, I would HIGHLY recommend you switch to the appropriate oil for the ambient temperatures to prevent oil starvation and pump wear during cold starts.
All I will say about this is. Just because "they" made a chart, does not make it fact, or true. Used to be we could say "you can research the world flat, don't make it flat" Now people believe that. I will continue to use my old fashioned 30 wt and be happy in all weather.
 

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All I will say about this is. Just because "they" made a chart, does not make it fact, or true. Used to be we could say "you can research the world flat, don't make it flat" Now people believe that. I will continue to use my old fashioned 30 wt and be happy in all weather.
flat earth is fairy tale people who cant handle basic science existing lol

Motor oils and their science is 1) very researched, very competitive, very regulated, and best of all, very profitable

Heres an easy way to understand this discussion
go find 3 quarts. 0w-30, 10w-30, and then sae 30 of the same brand, type if you can.

Go put them either in a really cold freeze for a long time, or use a cold stretch outside and just wait till its staying that temp long enough they all are that low temp, then open each one and pour a little into a container from each

You will notice the one just about doesnt pour and thats the SAE 30. (assuming its like -20, -15, -10 outside)
then you will notice there will be one that pours fastest, 0w-30
then you will notice one that doesnt flow well but way faster than the sae 30. 10w-30.T
The biggest issue with the SAE 30 part that isnt a conspiracy to get you(BTW sae 30 can bethe same price often as any other quart viscosity in my experience. so who they fleecing.

Anyway, the sae30 is detrimental the most for 1) crank speed 2) engine first starts up, ok, well if you have a non moving fluid that has to be pushed and beat up by moving parts to heat up enough to actually travel through the engine, you will experience more wear ever time that occurs. Cold start up. Most engine wear comes from that time.

Hydraulic lifters? someone may not have working valves as they should if its really bad bebcause of temps and stuff. starting may be a bitch then
 

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AuroraGirl is correct, start-ups are the hardest on engines, hence SYNTHETICS!!! All oil is good if it's clean & not broken down. Just stay away from parrafin based oils PERIOD!! The correct fuel supply/mixture is important also, not good to have your oil smell like fuel!
 

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Found this in my buddy's shop. He swears by this stuff, said he adds a quart every oil change.
Definitely gonna use this fir first start up, but will have to think about keep using it.
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Right and ecotec motors that tended to do that was an oiling system design flaw, and even then not all of them slugged up.

What I'm talking about. It gets worse the farther back you go, but pre-90 for sure. I remember even in the 80's my Dad was religious about his 3K oil changes and had some minor issues with sluge in his 350, and IH-345, but here my 305 is clean as a whistle inside. My 305 with 200K is still going, his 350 was getting tired after 100K, a lot of that. The longevity in engines as in general is thanks to improvements in oil detergents. We'd loose out on those improved detergents if we switched to high zinc engine oil.
Parrafin based oils were the main culprits of sludge, Pennz, Havoline, Quakerstate, etc... I've worked in the oilfield and have seen the difference in raw crude that comes straight out of the ground, as the parrafin wells had waxey-based crude and were generally a greenish color. My uncle bought a '75 K10 new and ran Pennzoil religously. My cousin & I rebuilt his motor at some point of it's life, and the inside was full of sludge.
 

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I will say this about the viscosity debate:
I have always used 10w30 in every car/truck/tractor/lawn mower, etc. that I own, for 3 reasons. 1) because that's what my dad always used, 2) because it seems to be the middle of the range between something like a 0w30 and a 15w40, and 3) because it's really nice and easy when something needs oil, to just grab THE jug I have on the shelf at home, and not have to worry about which one or is. Its convenient to have everything the same..

Temperature wise in my area, the hottest it's ever been was about °105, and the coldest it's ever been was about -°15. But those are the extremes. On average, the height of the summers are about °85, and coldest part of winter gets about °5-°10.
If everyone hear says it should 5w30 for my area, I'd have to believe you, in not an expert. I do want what's best for my engine.

As far as I understand the viscosity numbers, the 30 part is it's normal weight under normal circumstances, the smaller number is its weight in cold temperatures. Like any fluid, it gets thinner when it gets it gets warm and thicker when it gets cold. Please correct me if I'm wrong.
Now this is where everyone I meet seems to disagree, when the number gets smaller, does it get thicker or thinner? For example, is a "5" weight thinner or thicker than let's say a "15" weight at the same temp.

Also, a "thin" oil will not lubricate as well as a thicker one, correct? So wouldnt it be a good thing to have a thicker oil.

In the words of Mike Rowe, "Explain this to me as if I'm a small stupid child"
 

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I will say this about the viscosity debate:
I have always used 10w30 in every car/truck/tractor/lawn mower, etc. that I own, for 3 reasons. 1) because that's what my dad always used, 2) because it seems to be the middle of the range between something like a 0w30 and a 15w40, and 3) because it's really nice and easy when something needs oil, to just grab THE jug I have on the shelf at home, and not have to worry about which one or is. Its convenient to have everything the same..

Temperature wise in my area, the hottest it's ever been was about °105, and the coldest it's ever been was about -°15. But those are the extremes. On average, the height of the summers are about °85, and coldest part of winter gets about °5-°10.
If everyone hear says it should 5w30 for my area, I'd have to believe you, in not an expert. I do want what's best for my engine.

As far as I understand the viscosity numbers, the 30 part is it's normal weight under normal circumstances, the smaller number is its weight in cold temperatures. Like any fluid, it gets thinner when it gets it gets warm and thicker when it gets cold. Please correct me if I'm wrong.
Now this is where everyone I meet seems to disagree, when the number gets smaller, does it get thicker or thinner? For example, is a "5" weight thinner or thicker than let's say a "15" weight at the same temp.

Also, a "thin" oil will not lubricate as well as a thicker one, correct? So wouldnt it be a good thing to have a thicker oil.

In the words of Mike Rowe, "Explain this to me as if I'm a small stupid child"
The simplest way I can explain it is that the larger the number, the thicker the oil. SAE(Society of automotive engineers) has a set standard for measuring and grading oil viscosity. A number with a "w" is a multi-viscosity oil. The number with the "w" is the SAE viscosity measured at 0 degrees Fahrenheit. The number without a "w" is the viscosity measured at 100 degrees Celsius(boiling point of water or 212 degrees F at sea level). As with almost every fluid, the viscosity(thickness) of the oil will get thicker as the temperature gets lower.

All I will say about this is. Just because "they" made a chart, does not make it fact, or true. Used to be we could say "you can research the world flat, don't make it flat" Now people believe that. I will continue to use my old fashioned 30 wt and be happy in all weather.
Ah yes... the mysterious "they":happy175:.

"They" in this case, would be the Society of automotive engineers. You know, the same guys that developed the standard for measuring oil viscosity that you are using to determine the oil you are putting in your truck. It must, BY LAW, meet the numbers shown on that chart in order to even put that label on the jug. This does, by definition, make it true and a fact.

But you don't have to take anyone's word for it on the internet either. The best thing about this is that it is easily verified by a simple experiment that you can do at home. Go buy a quart of 5w-30 and a quart of SAE 30. Get two cups and two marbles. Stick the quarts of oil on your freezer for an hour. Pour them into the clear cups(you should easily be able to see why SAE 30 is a bad idea in freezing temps just from the pour, but its still fun to go all the way through the experiment). Drop a marble into each cup and watch how long it takes for it to fall to the bottom through both the SAE 30 and the 5W-30. You should see that the 5w-30 is about half the thickness of the SAE 30(it will still be pretty thick though).

Now put both quarts into a large pot of water and bring it to a boil(if you have a platform to go on the bottom of the pot for the quarts to rest on, otherwise do a double boil like you would to melt white chocolate). Do the same thing with the cups and marbles. You will find that the SAE 30 and 5w-30 have the exact same thickness at that temperature and the marbles fall to the bottom of the cup at the same speed.
 

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The simplest way I can explain it is that the larger the number, the thicker the oil. SAE(Society of automotive engineers) has a set standard for measuring and grading oil viscosity. A number with a "w" is a multi-viscosity oil. The number with the "w" is the SAE viscosity measured at 0 degrees Fahrenheit. The number without a "w" is the viscosity measured at 100 degrees Celsius(boiling point of water or 212 degrees F at sea level). As with almost every fluid, the viscosity(thickness) of the oil will get thicker as the temperature gets lower.
Okay, some of that makes sense and some doesnt.

Let's use for an example 5w 30.
So your saying the 5w is its weight at °0 and the 30 is its weight at °212?

And you said that the bigger the number is, the thicker it is. So how is it thicker at °212 than at °0? That doesn't make sense to me.

I may be dense, but something isn't adding up, unless I'm missing something obvious.
 

AuroraGirl

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an SAE 30 will, all things equal, be better for something that appropiately can use it temp wise. like a air cooled kohler k series. SAE 30 unless winter, 10w-30. if you had the benefit of starting in a warmed shop or a heater on the thing, you could rock the sae 30 all year since by time the engine is running the oil would be fine flow wise but where i live, nooooooo lol. but if I had a heater on it, sure, just dont forget because id hate to hear that noise startting lol

To my knowledge the temp stability with regards to shearing and evaporation rates, a single viscosity would be at advantage. but a high quality 10w-30 compared to a farm and fleet SAE 30 would probably beat it on those things too, gotta read your labels and specs and oil groups. Group III dinosaur syrup vs a group V scienced to **** synthetic is not apples to apples comparison to even a group iv to group v.. .etc.. basically, he lives in ND im pretty sure, he should use an oil pan heater if he keeps using sae 30 in my opinon and shelter it when not driving, but once its spring time, if he changes oil like i do, before winter after winter usually, you could use your sae 30 in the spring and go to a 5w-30 in winter. Where he lives, honestly, I would use 0w-30 and 5w-30 because my god cold cold

I used 0w-30 and 10w-30 exclusively in my car since i bought it and the 2nd oil change when i realized I wasnt burning any oil. :) I used 0w-40 since it was january and it was 208k miles but went down for fuel economy
 

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Okay, some of that makes sense and some doesnt.

Let's use for an example 5w 30.
So your saying the 5w is its weight at °0 and the 30 is its weight at °212?

And you said that the bigger the number is, the thicker it is. So how is it thicker at °212 than at °0? That doesn't make sense to me.

I may be dense, but something isn't adding up, unless I'm missing something obvious.
The confusion stems from you thinking the oil has a constant viscosity, which it obviously doesn't. A 5W-30 will haver the same viscosity at 0 degrees as a SAE 5 oil and the same viscosity as a SAE 30 at 212 degrees. Hence the term "multi-viscosity". Here is an image from a review question in one of my mechanical engineering textbooks that might give you a better visualization of what is happening. It has a pretty good reference to other liquids to give you a good idea of how SAE 30 basically becomes the consistency of tar at temps below zero.


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Its a linear line to help in visualizing what is happening though, since it wouldn't normally look linear like that. It is done that way by making the viscosity scale logarithmic, since the viscosity increases exponentially as the temps get colder. This means that the actual difference in viscosity on the hot side is infinitely smaller than it is on the cold side of the scale in that graph.
 

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The confusion stems from you thinking the oil has a constant viscosity, which it obviously doesn't. A 5W-30 will haver the same viscosity at 0 degrees as a SAE 5 oil and the same viscosity as a SAE 30 at 212 degrees. Hence the term "multi-viscosity". Here is an image from a review question in one of my mechanical engineering textbooks that might give you a better visualization of what is happening. It has a pretty good reference to other liquids to give you a good idea of how SAE 30 basically becomes the consistency of tar at temps below zero.


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Its a linear line to help in visualizing what is happening though, since it wouldn't normally look linear like that. It is done that way by making the viscosity scale logarithmic, since the viscosity increases exponentially as the temps get colder. This means that the actual difference in viscosity on the hot side is infinitely smaller than it is on the cold side of the scale in that graph.
You had me at the letters "log" and junior year algebra 2 said hello to my traumatic memory.

I recall passing algebra 2 and I recall passing the unit on logs but I also recall I couldnt ever figure out how to use a casio calculator for them as easily as a TI.

and then it gets fuzzy

I guess I won... at what cost... prob a passing grade but nothing to celebrate. Yeah.
 

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You had me at the letters "log" and junior year algebra 2 said hello to my traumatic memory.

I recall passing algebra 2 and I recall passing the unit on logs but I also recall I couldnt ever figure out how to use a casio calculator for them as easily as a TI.

and then it gets fuzzy

I guess I won... at what cost... prob a passing grade but nothing to celebrate. Yeah.
Basically what I'm trying to say is that its not a straight line of viscosity to temperature. It doesn't get 10 units thicker for every 10 degrees of temperature colder. It gets 10 TIMES thicker for every 10 degrees colder(not literally.. just a generalization). The actual relationship is a bit more complicated and involves logs, but is really not material to the conversation other than to say that the difference between SAE 10 and SAE 30 at 0 degrees is visually honey compared to tar. I would much rather try to push honey through my engine than tar.
 

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I will say this about the viscosity debate:
I have always used 10w30 in every car/truck/tractor/lawn mower, etc. that I own, for 3 reasons. 1) because that's what my dad always used, 2) because it seems to be the middle of the range between something like a 0w30 and a 15w40, and 3) because it's really nice and easy when something needs oil, to just grab THE jug I have on the shelf at home, and not have to worry about which one or is. Its convenient to have everything the same..

Temperature wise in my area, the hottest it's ever been was about °105, and the coldest it's ever been was about -°15. But those are the extremes. On average, the height of the summers are about °85, and coldest part of winter gets about °5-°10.
If everyone hear says it should 5w30 for my area, I'd have to believe you, in not an expert. I do want what's best for my engine.

As far as I understand the viscosity numbers, the 30 part is it's normal weight under normal circumstances, the smaller number is its weight in cold temperatures. Like any fluid, it gets thinner when it gets it gets warm and thicker when it gets cold. Please correct me if I'm wrong.
Now this is where everyone I meet seems to disagree, when the number gets smaller, does it get thicker or thinner? For example, is a "5" weight thinner or thicker than let's say a "15" weight at the same temp.

Also, a "thin" oil will not lubricate as well as a thicker one, correct? So wouldnt it be a good thing to have a thicker oil.

In the words of Mike Rowe, "Explain this to me as if I'm a small stupid child"
You have already gotten a great explanation on the oil weights, but I agree that having only a single weight or limited on had is very nice. Here in the PNW we rarely get extreme cold. My wife has a 05 van that calls for 5W20 and I've run synthetic 5W20 in it since day one, so I continue to do that. Everything else gets 15W40 dual rated "heavy duty" oil, commonly called diesel oil. Why because the diesel equipment on the farm needs it, and it's pretty close to 10W30, heck my owners manual for my square even says I can run it down to I think 15F and we so rarely get that cold so I don't really worry to much about that.
 
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