A good read on motor oil

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Steve, There are some members here with less than a half century of living here, aren't there? The viscosity used is not a function of wanting to see a specific oil pressure. It is a function of bearing clearance and intended use, and sometimes specific "needs". I would not put 5w/anything in engine of this vintage, the clearances are too big for that, not to mention runout tolerances on cranks and rods. If the MEASURED bearing clearances are very close to factory specs and usage is not abusive, 10W30 should be fine. if the tolerances are a bit looser, a 10W40 may be the right pick. 10W40 might be the right pick for factory specs for an engine that is going to be "leaned on" frequently. I certainly could be wrong but, I think 20W50 should be reserved for pretty loose tolerances and or race applications. The 0W20 oil for these new cars is driven by the need to extract the last .001% of MPG by OEMs and VERY tight tolerances. I have a 2020 vehicle that calls for 5W30 and I use 5w40 for a little extra protection when it is 100 degrees and I decide I want to drop the hammer. I run a high volume, high pressure oil pump in a 331W with a solid roller cam in a street car (specific needs). I wanted the volume based on the slightly loose tolerances, significant RPMs, and the pressure to make the solid roller lifters live with significant time idling. That car has been on the street since 2000. Albeit with few miles per year. That is just one old geezer's take on the subject. Chuck
 
So I looked into this question last year and found an interesting article about it. It looks like Shell engineers actually recommend Rotella for classics. The MT article notes that Diesel oils are intended for lower RPMs than gas engine oils. So what's the problem? Big old V8s run at much lower RPMs than modern engines, which are what the modern gas engine oils are formulated for. I suspect this is why Shell oil engineers recommend Rotella for many classis:

https://www.hagerty.com/media/archived/engine-oil-tips-from-the-experts-at-shell/
This article also provides a phone number to get a personalized recommendation from Shell: 1-800-BEST-OIL

Happy oiling!
 
A couple of years ago, I was refreshing my memory on the flat-tappet lifter failure debate. I cam across an article (I think it was published by Motor Trend) that had a comment saying that "insert company name here" oil company does not recommend their full synthetic with flat tappet cams. I recall that I went to said mfg's web site and was able to locate and read the recommendation for myself. I'm pretty sure it was Quaker State that was named, but I've been unable to find either the article or the recommendation. Did any of you happen to read that article?
 
Cleveland Crush said:
I read that article. I believe they said no synthetic during "break in" but otherwise it's fine.
Click to expand...
Yeah, I've seen the break in statement made a number of times...this was was an overall recommendation by the manufacturer. I'll keep on the lookout and post it up if I find it.
 
I found a MTrend article, it mentions synthetic after cam break in.
I've put about 30,000 miles on my Cleveland with performance cam and valve springs, and didn't know about zinc, so my lobes are probably worn down. A part of the article:
" If the lifter stops turning, the cam lobe wears on the same area of the lifter and both wear down soon thereafter. Synthetic oils are so slippery that there is less force to turn the lifter. So, theoretically, synthetic oil could cause problems for flat-tappet cams.
The real-world warning comes from cam manufacturers. Who has better experience than the people who make cams, test them, and learn of failures because they warranty them? Major aftermarket cam manufacturers state not to use synthetic oil during break-in, and one states not to use synthetic oil for at least 5,500 miles after break-in of flat-tappet cams."
 
Yep, "generally" agree with stated article, BUT many, many times no problem using synthetic oil during break in. Just because so many variables involved. Pull your intake and a couple of lifters and take a look to see how things look. I'll give you good odds all is OK!
 
Usually, higher zink oils offer the least amount of ware protection. Most of the time adding zink only will promote more ware. Zink additional/high zink is advertising filmic by junk oil companies.

Diesel oils offer very modes protection compared to automotive oil as it is designed for low rpm range. Proven by PSI film strenth.

For example : Bred Pen oil (high on zink) has guaranty lobe ware in clasic cars.

Those who switched to #1 ranked oil film strenght (ware protection) having no issues, even though it's a full suntetic 5w30 in clasic car engine - Quate State.

If you have time, read it...the most comprehensive testing you will fin on oils:
https://540ratblog.wordpress.com/
 
" If the lifter stops turning, the cam lobe wears on the same area of the lifter and both wear down soon thereafter. Synthetic oils are so slippery that there is less force to turn the lifter. So, theoretically, synthetic oil could cause problems for flat-tappet cams.
Lifter rotation is not caused by the oil. It is caused by the slight crown on the bottom of the lifter and the slight taper on the cam lobe. Chuck
 
YellowHorse said:
Usually, higher zink oils offer the least amount of ware protection. Most of the time adding zink only will promote more ware. Zink additional/high zink is advertising filmic by junk oil companies.

Diesel oils offer very modes protection compared to automotive oil as it is designed for low rpm range. Proven by PSI film strenth.

For example : Bred Pen oil (high on zink) has guaranty lobe ware in clasic cars.

Those who switched to #1 ranked oil film strenght (ware protection) having no issues, even though it's a full suntetic 5w30 in clasic car engine - Quate State.

If you have time, read it...the most comprehensive testing you will fin on oils:
https://540ratblog.wordpress.com/
Click to expand...
Very long and interesting read. Do other members believe the claims that we should all use only Quaker State 5W30 full synthetic and nothing else in our cars and chuck ZDP entirely? The research sounds legit.
 
I read the article too. Lots of info, takes a long, long time to read. I'm happy to see my preferred oil rates "outstanding" (Mobil 1 15-50). But kevken you asked my opinion of the article...:
"540-RAT" the researcher/author and self professed god of all engines is a blowhard! He literally states anyone who does not follow  his research/recommendation to ONLY use Pennzoil 5-30 synthetic IN ALL ENGINES ALL THE TIME is an idiot; not my words but 540-RATS.
I guess if someone feels "540-RAT" has more lubrication insight then engineers at Exxon-Mobil, Valvoline, Castrol, NASCAR Cup crew chiefs, Rouch Racing, and countless other professionals... then follow his decree and only use Penzoil 5-30!!!
 
kevken1959 said:
Very long and interesting read. Do other members believe the claims that we should all use only Quaker State 5W30 full synthetic and nothing else in our cars and chuck ZDP entirely? The research sounds legit.
Click to expand...
I have tested engine oil multiple times after 6k mi change intervals (black stone labs) from by twin turbo 3.5L ford explorer which I run hard (has ECU tune and sees redline almost daily).
Saw much better ware results with QS vs Mobile 1 - just like his research shows.
I am not saying 5w30 QS will be fit for all, as worn out engines might spring leaks and might not have correct pressure. Old worn engine might be better off with 5w40 (just look up wich test better on his report).
There is no reason to go with 10w weight ...and yes, sink additive is snake oil very likely will cause damage. Juts use good oil.

Mobil 1 fails quickly at hight tems while QS handles high tems the best.
 
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YellowHorse said:
Usually, higher zink oils offer the least amount of ware protection. Most of the time adding zink only will promote more ware. Zink additional/high zink is advertising filmic by junk oil companies.

Diesel oils offer very modes protection compared to automotive oil as it is designed for low rpm range. Proven by PSI film strenth.

For example : Bred Pen oil (high on zink) has guaranty lobe ware in clasic cars.

Those who switched to #1 ranked oil film strenght (ware protection) having no issues, even though it's a full suntetic 5w30 in clasic car engine - Quate State.

If you have time, read it...the most comprehensive testing you will fin on oils:
https://540ratblog.wordpress.com/
Click to expand...
I have mix feelings reading this blog. I have not gone through it since he spends way too much time bashing whoever doesn't believe him. As an engineer I know that typically one person is not always correct. This guy writes in a way that turns me off. He brags too much for my taste. I am not saying he may not have some good points. All I am saying that he should write about his test results and opinions, and stop using cap letters and bashing others.
 

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