Merkava, the viscosity curve is not linear. You can't just use an average.
why was 10W-40 so popular back in the 1960's?
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Originally Posted By: Quattro Pete
By the same token you could say that a 30 grade is really a 20 grade or even a 10 grade "in between full cold and full hot," but so what?
Trying to follow Merkava's flawed logic, I noticed I made a mistake in the above statement. It should have said:
Quote:
By the same token you could say that a 30 grade is really a 40 grade or even a 50 grade "in between full cold and full hot," but so what?
Still, I repeat, this train of thought goes nowhere. The whole SAE grading system is based on a reference temperature (100C), and not "in between full cold and full hot."
The other reference temperature is for the "Xw", so it is -35C, -30C, -25C, -20C, and -15C for 0w, 5w, 10w, 15w, and 20w, respectively.
By the same token you could say that a 30 grade is really a 20 grade or even a 10 grade "in between full cold and full hot," but so what?
Trying to follow Merkava's flawed logic, I noticed I made a mistake in the above statement. It should have said:
Quote:
By the same token you could say that a 30 grade is really a 40 grade or even a 50 grade "in between full cold and full hot," but so what?
Still, I repeat, this train of thought goes nowhere. The whole SAE grading system is based on a reference temperature (100C), and not "in between full cold and full hot."
The other reference temperature is for the "Xw", so it is -35C, -30C, -25C, -20C, and -15C for 0w, 5w, 10w, 15w, and 20w, respectively.
My dad hated, and I do mean hated, multi vis oils. Never gave a solid reason why. He was profoundly a straight weight oil guy. He used 30w religiously for years and years, winter or summer. My whole time growing up till I went in the Army in the early 70's and long after, he used only 30w oil, specifically Archer Petroleum brand (a regional brand that primarily targets agriculture users). Took a lot of vehicles, both business and personal, to well over 200,000 miles using only a 30w oil. As a youngster, it was hard to refute that kind of evidence.
Originally Posted By: TiredTrucker
My dad hated, and I do mean hated, multi vis oils. Never gave a solid reason why. He was profoundly a straight weight oil guy.
My dad was the opposite, and adopted multigrades as soon as they became available, and thinner ones, too. He detested "thick garbage" as he called it.
My dad hated, and I do mean hated, multi vis oils. Never gave a solid reason why. He was profoundly a straight weight oil guy.
My dad was the opposite, and adopted multigrades as soon as they became available, and thinner ones, too. He detested "thick garbage" as he called it.
I think Merkava and Archie Bunker might have a lot in common
Originally Posted By: Quattro Pete
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
Originally Posted By: Ducman
Here in OZ 10w-40's and 20w-40's were the norm through to the 80's for our locally built cars. Naturally there was always/is the standard 15w-40 HDDO.
I think 10w-40 is still the current grade for one locally built turbo l6 engine still in production.
Funny, I grew up in a different Oz...
20W-50 was the staple everywhere. GTX, XLD,
Shell were strange with Super SF 20W-40, and XMO (15W-30...wish that gradewas still around)
BP had Corse, 25W-50.
Duckhams had 15W-50, which was green, and odd.
M1 was 15W-50.
Each manufacturer made limited offerings, not many 15W-40s were plain petrol rated.
Then late 80s, they all went stupid.
STP, and Penrite started their 20W-70 stories, BP Corse went 25W-60, people started with 80s etc.
Here in OZ 10w-40's and 20w-40's were the norm through to the 80's for our locally built cars. Naturally there was always/is the standard 15w-40 HDDO.
I think 10w-40 is still the current grade for one locally built turbo l6 engine still in production.
Funny, I grew up in a different Oz...
20W-50 was the staple everywhere. GTX, XLD,
Shell were strange with Super SF 20W-40, and XMO (15W-30...wish that gradewas still around)
BP had Corse, 25W-50.
Duckhams had 15W-50, which was green, and odd.
M1 was 15W-50.
Each manufacturer made limited offerings, not many 15W-40s were plain petrol rated.
Then late 80s, they all went stupid.
STP, and Penrite started their 20W-70 stories, BP Corse went 25W-60, people started with 80s etc.
Originally Posted By: Merkava_4
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
101 states that a multigrade starts as the W number, and is thickened to the top...e.g. 10W-30, and 10W-40 start as a 10W, and are thickened to the top end.
It's plain wrong.
You seem to be following a similar line, but using KV40 as the basis...it's novel and unique, but the points that define 30, 40, and 50, are the viscosity at 100C.
Like I said, I get where you are going, but it's got nothing to do with the actual viscosity that the bearing sees...which is high shear, at a temperature of 100-130C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
101 states that a multigrade starts as the W number, and is thickened to the top...e.g. 10W-30, and 10W-40 start as a 10W, and are thickened to the top end.
It's plain wrong.
You seem to be following a similar line, but using KV40 as the basis...it's novel and unique, but the points that define 30, 40, and 50, are the viscosity at 100C.
Like I said, I get where you are going, but it's got nothing to do with the actual viscosity that the bearing sees...which is high shear, at a temperature of 100-130C.
Originally Posted By: Merkava_4
Originally Posted By: Quattro Pete
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
I'm out. It's like speaking to a brick wall.
Originally Posted By: Quattro Pete
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
I'm out. It's like speaking to a brick wall.
Going by the evidence of my job at Advance, 10w-40 is still the most popular grade. 20-50 gives it a good run, though.
Customer: "What kind of oil my car take?"
Me: "Your 2013 Prius takes 0-20."
Customer: "That's too thin!" *grabs 20-50 and a quart of Lucas*
Customer: "What kind of oil my car take?"
Me: "Your 2013 Prius takes 0-20."
Customer: "That's too thin!" *grabs 20-50 and a quart of Lucas*
My 1984 Jeep Cherokees 2.8V6, 1985 Grand Wagoneers 360V8 and 1993 Grand Cherokees 318V8 All have ND, yes ND30, in them. at least 50% 0f crankcase worth.
Western Family ND30 Is too thin! Well, its good for winter time around here. I prefer Accel ND30,...its thick,..when cold,..for my V8s. Almost Never for a Inline6, though...
Originally Posted By: Quattro Pete
Originally Posted By: Merkava_4
Originally Posted By: Quattro Pete
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
I'm out. It's like speaking to a brick wall.
+1
Originally Posted By: Merkava_4
Originally Posted By: Quattro Pete
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
I'm out. It's like speaking to a brick wall.
+1
My father was a big 10w40 guy for years he ran Oilzum brand in the cans then Sears Spectrum. I recall him putting it in his Ford station waggon 390 V8 and Boss 302 Mustang. He ran both for years and many miles without issue so he must have been doing something right. Today he runs only 10w30 and mostly Formula Shell conventional and everything he owns runs great. He often tells me I overthink my oil choice. He follows the old "Run whatcha brung" and don't worry about it just change it plus the filter between 4-5,000 miles.
I worked in a Mobil station back in the '70s. What pushed the 10W-40 was probably mostly marketing and "thicker is better" mindset. Straight 30 weight wasn't popular probably because it caused hard starting in the winter. I tried it once, only once, it started very hard during a cold snap.
If anyone needed oil, we'd just naturally ask if they wanted the Super (it must be the best, it's super). Yeah it was a little more expensive, but not by much. I think we honestly thought we were giving the customer a better oil. Nobody ever had a problem with it.
The 10W-40 was "Super" in a full gold can:
The 10W-30 was "Special" in a half gold, half white Can:
And the straight 30 weight was "Heavy Duty" in a half blue, half white can:
Obviously... the gold can was "best".
(It was fun looking up the old cans.)
If anyone needed oil, we'd just naturally ask if they wanted the Super (it must be the best, it's super). Yeah it was a little more expensive, but not by much. I think we honestly thought we were giving the customer a better oil. Nobody ever had a problem with it.
The 10W-40 was "Super" in a full gold can:
The 10W-30 was "Special" in a half gold, half white Can:
And the straight 30 weight was "Heavy Duty" in a half blue, half white can:
Obviously... the gold can was "best".
(It was fun looking up the old cans.)
Last edited:
Originally Posted By: Quattro Pete
Originally Posted By: Merkava_4
Originally Posted By: Quattro Pete
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
I'm out. It's like speaking to a brick wall.
haha see? archie bunker!
Originally Posted By: Merkava_4
Originally Posted By: Quattro Pete
But the "40" has nothing to do with cold. The "40" is only in reference to viscosity at 100C temperature.
A 10w-40 is a 40 grade when at 100C, just like SAE30 is a 30 grade at 100C.
Valvoline SAE30
86.5 cSt @ 40*C
Valvoline SAE40
140 cSt @ 40*C
Valvoline 10W-30
69.7 cSt @ 40*C
Valvoline 10W-40
95.4 cSt @ 40*C
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
I'm out. It's like speaking to a brick wall.
haha see? archie bunker!
Originally Posted By: Merkava_4
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
Merk, why are you being stubborn about this? Read SAE J300. Better yet, here's a chart for you, so you don't even have to look it up.
Now, where on that chart is there any reference to KV40? The KV40 is as irrelevant as CCS or MRV numbers for determining whether it's a 30 or a 40.
You simply cannot decide to use whatever temperature you wish to use to determine grade. SAE 30 is like a brick at -40, whereas a 5w-50 or a 0w-40 will still be usable.
So, if we can cherry pick temperatures, I arbitrarily define SAE 30 as a grease in a Saskatchewan winter, rather than a motor oil, and hereby direct that the API stop licensing it. I'm sure that'll go well.
It's looking to me like SAE30 is closer to 10W-40 at 40*C (104*F) than it is to 10W-30 at 40*C (104*F).
Therefore, 10W-40 is a 30 weight oil.
Merk, why are you being stubborn about this? Read SAE J300. Better yet, here's a chart for you, so you don't even have to look it up.
Now, where on that chart is there any reference to KV40? The KV40 is as irrelevant as CCS or MRV numbers for determining whether it's a 30 or a 40.
You simply cannot decide to use whatever temperature you wish to use to determine grade. SAE 30 is like a brick at -40, whereas a 5w-50 or a 0w-40 will still be usable.
So, if we can cherry pick temperatures, I arbitrarily define SAE 30 as a grease in a Saskatchewan winter, rather than a motor oil, and hereby direct that the API stop licensing it. I'm sure that'll go well.
Back to the original question. Most of my friends used 20w-50 Castrol. We used it in our street cars, pu trucks, motorhomes, race cars and boats. And what was left over went into the lawn mower.
Quote:
Now, where on that chart is there any reference to KV40? The KV40 is as irrelevant as CCS or MRV numbers for determining whether it's a 30 or a 40.
Garak
Curious choice of table to illustrate your point. KV40 figures do appear in 3 columns to KV100 in two columns. Anyway this seems to be an old J300 table, the CCS and Pumping figures are now quite different. Typically confusing table that almost inplies that the KV40 figures apply to the SAE grades which I assume they do not.
Of course Merkava is confusing the actual viscosity at some temperature with defined standard. A SAE 30 oil has a viscosity between 9.3 and 12.5 cST at 100C and a 10W40 is between 12.5 to 16.3 cST at 100C. That's it, end of. The fact that the 30 oil starts thinner and eventually becomes thicker than the 10W40 at some lower temperature is irrelevant to what you call the oil.
Now, where on that chart is there any reference to KV40? The KV40 is as irrelevant as CCS or MRV numbers for determining whether it's a 30 or a 40.
Garak
Curious choice of table to illustrate your point. KV40 figures do appear in 3 columns to KV100 in two columns. Anyway this seems to be an old J300 table, the CCS and Pumping figures are now quite different. Typically confusing table that almost inplies that the KV40 figures apply to the SAE grades which I assume they do not.
Of course Merkava is confusing the actual viscosity at some temperature with defined standard. A SAE 30 oil has a viscosity between 9.3 and 12.5 cST at 100C and a 10W40 is between 12.5 to 16.3 cST at 100C. That's it, end of. The fact that the 30 oil starts thinner and eventually becomes thicker than the 10W40 at some lower temperature is irrelevant to what you call the oil.
Last edited:
Originally Posted By: Boxnuts
Of course Merkava is confusing the actual viscosity at some temperature with defined standard. A SAE 30 oil has a viscosity between 9.3 and 12.5 cST at 100C and a 10W40 is between 12.5 to 16.3 cST at 100C. That's it, end of.
+1
By the way, here is a more recent SAE J300 table:
Of course Merkava is confusing the actual viscosity at some temperature with defined standard. A SAE 30 oil has a viscosity between 9.3 and 12.5 cST at 100C and a 10W40 is between 12.5 to 16.3 cST at 100C. That's it, end of.
+1
By the way, here is a more recent SAE J300 table:
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