motor oil
Burning Brakes
Joined: Jan 2006
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From: Fort Wayne IN
Le Mans Master
Joined: Jun 2019
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From: Loveland
It depends on which engine and year you are talking about. The 68 327 doesn't list anything over 30W. Maybe later years have a wider range. There isn't one size fits all. People need to know their own car.
Burning Brakes
Joined: Dec 2021
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I have been using straight 10w-30 cheapest oil I can find for years in all the muscle cars I have owned .. never had a problem !! Just change oil once a year regardless of mileage ..This is just my opinion another way for the manufacturers to make money
Le Mans Master
Joined: Apr 2011
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From: Hermosa
40w is where it’s going to be under running conditions once it’s up to temperature.
I don’t know why on these motors anyone believes the the bearing clearances are anywhere close to where they were when assembled or even specd for during the design phases. You’ve likely got more than adequate clearances to run straight 50 wt if you wanted to on any motor over 50,000 miles. This is 1960’s tech not 2022.
I run mine on 0w-40 after a rebuild even with stock clearance specs. Run it hard and up to 6300 rpm.
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Le Mans Master
Joined: Jun 2019
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From: Loveland
So you are saying the oil is 0 weight when cold? The 0 stands for 0*. It means the oil will react down to 0 degrees at a specific weight, but that weight is only found in the technical numbers.
0W stands for 0* Winter.
0W stands for 0* Winter.
Last edited by kodpkd; Jun 2, 2022 at 02:20 PM.
Melting Slicks
Joined: Sep 2007
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From: cary Il
Le Mans Master
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From: Loveland
Yes basically.
10W-30 means at 10* the oil maintains a certain viscosity,,,, and at 100* it maintains a certain viscosity. The spec of the oil is designed around those numbers. A straight 30 weight oil gets thicker when it drops to 10* than a 10W-30 oil. That is the magic of the new multi viscosity oils. The weight of the oil is totally different than the viscosity. Every oil changes viscosity with temperature, the hotter it is, the less the viscosity, the colder it is the thicker the viscosity. But it is still a 30 weight oil. It can't be any other way. A 10W-30 has specific design specs which is different than 5W-30 oil. OIL 101.
10W-30 means at 10* the oil maintains a certain viscosity,,,, and at 100* it maintains a certain viscosity. The spec of the oil is designed around those numbers. A straight 30 weight oil gets thicker when it drops to 10* than a 10W-30 oil. That is the magic of the new multi viscosity oils. The weight of the oil is totally different than the viscosity. Every oil changes viscosity with temperature, the hotter it is, the less the viscosity, the colder it is the thicker the viscosity. But it is still a 30 weight oil. It can't be any other way. A 10W-30 has specific design specs which is different than 5W-30 oil. OIL 101.
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Straight from Google:
The first digit is the oil viscosity at 0* (zero degrees)
The second digit is the oil viscosity at 212* (two hundred twelve)
Most motor oil runs at 210*.
And I don't see how a straight 30w is going to get thicker at colder temps. It should maintain 30w regardless of temps. And that was always a problem decades ago.
Early oils were changed to thinner / thicker with the season changes. Winter oil / summer oil. Eventually the invention of the multigrade cured that issue.
The first digit is the oil viscosity at 0* (zero degrees)
The second digit is the oil viscosity at 212* (two hundred twelve)
Most motor oil runs at 210*.
And I don't see how a straight 30w is going to get thicker at colder temps. It should maintain 30w regardless of temps. And that was always a problem decades ago.
Early oils were changed to thinner / thicker with the season changes. Winter oil / summer oil. Eventually the invention of the multigrade cured that issue.
Last edited by HeadsU.P.; Jun 3, 2022 at 07:18 PM.
Le Mans Master
Joined: Jun 2019
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From: Loveland
Straight from Google:
The first digit is the oil viscosity at 0* (zero degrees)
The second digit is the oil viscosity at 212* (two hundred twelve)
Most motor oil runs at 210*.
And I don't see how a straight 30w is going to get thicker at colder temps. It should maintain 30w regardless of temps. And that was always a problem decades ago.
Early oils were changed to thinner / thicker with the season changes. Winter oil / summer oil. Eventually the invention of the multigrade cured that issue.
The first digit is the oil viscosity at 0* (zero degrees)
The second digit is the oil viscosity at 212* (two hundred twelve)
Most motor oil runs at 210*.
And I don't see how a straight 30w is going to get thicker at colder temps. It should maintain 30w regardless of temps. And that was always a problem decades ago.
Early oils were changed to thinner / thicker with the season changes. Winter oil / summer oil. Eventually the invention of the multigrade cured that issue.
Even multi grade oil,,,, still gets thicker the colder it is.
"The first digit is the oil viscosity at 0* (zero degrees)" Not true.
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Don't argue with me. Argue with Google and the oil experts.
Lab test conducted on oils are set at to specific temperatures to determine viscosity:
Zero degrees Fahrenheit and 212 degrees Fahrenheit.
Lab test conducted on oils are set at to specific temperatures to determine viscosity:
Zero degrees Fahrenheit and 212 degrees Fahrenheit.
Le Mans Master
Joined: Jun 2019
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From: Loveland
I totally agree. But you said,,,,, "And I don't see how a straight 30w is going to get thicker at colder temps. That is crazy.
That would be a chemical engineers dream come true.
It is actually, 0*C and 100*C
That would be a chemical engineers dream come true.
It is actually, 0*C and 100*C