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Castrol oil again

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"Lifetime free oil changes" sounds good to me. If there is an oil-related failure, then it's Ford's problem.

At one of the tech sessions a couple of years ago, a well-versed and trusted presenter was asked what oil re recommended in a newly rebuilt Austin engine. His reply was "Whatever the engine rebuilder says. That way, if it fails it's the rebuilder's problem."
 
Thanks, Doug. Both the QS and Valvoline look like good oil for the money. For what I dropped on that car I'm actually not too concerned about the price of oil; for once I'm more worried about staying in warranty (there are apparently some issues with the Coyote engine).
 
Hi All,

The more I read the 540 RAT Blog, the more I learn and the more I become confused.

We commonly use 20W50 oils today and, based upon the benefits presented from flow, wonder if our choice is the best for our engines. As I remember, in the early days 10W30 was used in my new Healey and a while after 10W40 was selected when commonly available to increase my gauge oil pressure. As time passed, it seems that the perception of having good oil pressure became synonymous with good engine performance and health and the definition of "Resistance to Flow" was lost. I am wondering if going back to 10W30(or 40) or even 5W30(or 40) could prove more beneficial … especially with a high PSI.

What are your thoughts?
Ray(64BJ8P1)
 
RAC68 said:
What are your thoughts?
Ray(64BJ8P1)
Click to expand...

My thoughts are I'm confused as well, and I've heard the flow vs. pressure argument elsewhere. I've always thought that the higher the oil pressure the better but, like ZDDP content, can there be too much? I've noticed the oil pressure in my Healeys is 'nominal;' i.e. 15-20PSI at hot idle and 45 or so at speed. I think 20W-50 is probably OK with an older engine that was constructed with larger clearances and tolerances and, at any rate, I've got a couple cases of 20W-50 which I'll use up before making any change. My new car has a (real) oil pressure gauge and, though I haven't paid too much attention to it, gives the same pressure readings as the Healeys, with 5W-20 oil.

Historically, people have thrown shade on 10W-40 oil as, apparently, the viscosity range is so large that too much viscosity improvers were used, which are prone to breaking down (shearing) over time. IIRC BMW once said using 10W-40 would void their warranty, though I think now some of their cars use a 0W-60 oil.
 
RAC68 said:
Hi All,

The more I read the 540 RAT Blog, the more I learn and the more I become confused.

We commonly use 20W50 oils today and, based upon the benefits presented from flow, wonder if our choice is the best for our engines. As I remember, in the early days 10W30 was used in my new Healey and a while after 10W40 was selected when commonly available to increase my gauge oil pressure. As time passed, it seems that the perception of having good oil pressure became synonymous with good engine performance and health and the definition of "Resistance to Flow" was lost. I am wondering if going back to 10W30(or 40) or even 5W30(or 40) could prove more beneficial … especially with a high PSI.

What are your thoughts?
Ray(64BJ8P1)
Click to expand...
The recommendation for 20W50 is in Section Q (Lubrication) of the Bentley manual. 20W40 is also suggested, especially for lower temperatures.
 
Bob_Spidell said:
My thoughts are I'm confused as well, and I've heard the flow vs. pressure argument elsewhere. I've always thought that the higher the oil pressure the better but, like ZDDP content, can there be too much? I've noticed the oil pressure in my Healeys is 'nominal;' i.e. 15-20PSI at hot idle and 45 or so at speed. I think 20W-50 is probably OK with an older engine that was constructed with larger clearances and tolerances and, at any rate, I've got a couple cases of 20W-50 which I'll use up before making any change. My new car has a (real) oil pressure gauge and, though I haven't paid too much attention to it, gives the same pressure readings as the Healeys, with 5W-20 oil.

Historically, people have thrown shade on 10W-40 oil as, apparently, the viscosity range is so large that too much viscosity improvers were used, which are prone to breaking down (shearing) over time. IIRC BMW once said using 10W-40 would void their warranty, though I think now some of their cars use a 0W-60 oil.
Click to expand...
Flow is more important than pressure; pressure is an indication that you have "enough" for flow. It's really hard (read expensive) to put in an oil flow rate meter.

Toward the bottom of the 540 RAT blog is a discussion of BMW rod bearing failures. He says that BMW didn't design the rod clearances for thicker oils.
 
High John/All,

I must admit, I haven't looked at Section Q of the manual but also remember that, at the time, 10W30 was what most cars used and what the dealer used, and told me to use, in my Healey.

I still reiterate, if PSI is a main indicator of an oil's protection and a thinner oil would benefit our engine's as outlined in the 540 RAT, isn't it logical that we select an oil with good PSI ratings and has a lower viscosity the that of a 20W50. Additionally, it appears the benefits of a synthetic lubricant may have been over expressed and a mineral oil a better and less expensive choice. So, based upon these factors, a mineral oil with a PSI in the 90K range and a viscosity of 10WX or even 5WX should be considered and may be our best choice. Additionally, an oil designed for high mileage engines could address the greater spacing of our engine components (compared to new engines designs).

So, again, your thoughts and which oils do you feel would satisfy these criteria best,
Ray(64BJ8P1)
 
Hi Ray,

Given that BMC recommends an oil with a viscosity of 20W50 or 20W40, 540 RAT's suggestion that a lower viscosity is better for more flow, the wear protection PSI should be as high as possible, and high mileage oils for those engines with high mileage, the highest PSI oil that fits all those is: "41. 10W40 Valvoline MaxLife High Mileage, API SN, synthetic blend (red bottle) = 103,840 psi."

If you want add conventional (dino) oil to those requirements, your choice becomes "63. 10W40 Pennzoil High Mileage Vehicle, API SN, conventional = 97,419 psi."

If your oil pressure is still in excess of 10 psi per 1,000 RPM, you could try a xW30 oil, "46. 5W30 Pennzoil High Mileage Vehicle, API SN, conventional = 102,402 psi." This is a conventional oil instead of a blend.
 
Some of you guys must have way way way too much time on your hands to google and read and re read and research and digest ,diagnose all this oil flin flan .
Put some 20/50 in it and drive it like ya stole it .
Healey engines are pretty much bullet proof . :eagerness::eagerness:
 
Healey Nut.
It seems not everyone is convinced that 20W50 is optimal.
And there are a lot of poorly performing oils on the market, per 540ratblog.
YMMV.
Douglas
 
Healey Nut said:
Some of you guys must have way way way too much time on your hands to google and read and re read and research and digest ,diagnose all this oil flin flan .
Click to expand...

It's 'flim flam' and, yeah, I read a lot, and I like learning new stuff (and even re-learning old stuff).
 
Thanks John,

Also, it is economically pleasing as well. A 5qt container at Walmart of 10W40 Valvoline MaxLife High Mileage is a few pennies more then $17 (+tax) and much less then most other choices. Although I still have a sufficient quantity for another Mobil 1 15W50 change, I am thinking of using the Valvoline at my next change planned for mid summer (recently changed oil before winter shut-down).

Last, when reviewing section Q of the Bentley manual, it should be considered that the formulation of oils when the recommendation was made was quite different then what is available today and, I believe, should only be taken as a historic reflection and is not matched as a modern specification. When reviewing the 540 RAT, it was somewhat disheartening to see the changes in test results of some of the oils previously tested with more positive results.

Ray(64BJ8P1)​

 
Ray,

The formulations between 1953 - 1967 and today are certainly different, but SAE viscosity specifications haven't changed. What has changed regarding viscosity is the improvement in viscosity modifiers and synthetic oils so that wider cold vs. hot viscosity ranges are possible and more likely to remain over the life of the oil.
 
John,

Yes, the definition and means of determining an oil's viscosity are likely the same since the '60s. However, as you have mentioned, the additive package and other physical factors as PSI have changed greatly. Prior, I only looked at the Oil Can Lable and manufacturer's hype to select my automotive oils. Now I am looking at PSI as a main factor in my selection and one of a few selection criteria I am more aware of after reading 540 RAT.

So, even though SAE Viscosity may mean the same since the '60s, the oil's performance has drastically changed and comparing and selecting oil based upon viscosity has become much less of an apples to apples comparison. So, although I would have happily followed Healey Nut" suggestion to "
Put some 20/50 in it and drive it like ya stole it ", today I am aware not all 20W50 oils are desirable or equally as protective of my Healey's engine.​

Ray(64BJ8P1)
 
John Turney said:
It's called "no longer having to work for a living."
Click to expand...

Oh I get that but even when I reach that point (four more years) I will still put in the Castrol 20/50 and drive it like I stole it ..
I simply have better things to spend my time on than reading all the oil flin flan and snake oil BS . Its all marketing hype .
I will be in the shop tinkering oiling greasing and polishing instead of glued to a screen reading endless marketing hype .
 
TH: Use Valvoline VR1 of your viscosity choice and don't worry none.--LOL
 
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