Can thicker oil prevent rocker arm failures in Pentastar 3.6 V6?

Bill_W said:
The video says AN has comparable POE affect with seal swell. I kinda wonder why they have all three base oils in a few Mobil 1 oils?
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I don't think that's accurate, based on what I've read about AN's. POE has a heavy impact on seal swell. AN's are far closer to neutral on seals (while still having some seal swell tendencies).

I'd highly recommend reading this paper from the STLE, which I shared in my thread on Dr. Rudnick:

There's also this presentation from Chevron:

Which features the following table:
Screen Shot 2022-05-26 at 7.24.28 PM.png


Which notes that esters cause seal swell, while AN's have less impact on seals than esters.

Esters do have some advantages, and Mobil's POE esters have much higher VI's than their AN's, so the combination of the three bases (originally called "tri-syn") was designed to capitalize on the strengths of all three bases, while neutralizing their weaknesses.
 
OVERKILL said:
Oxidation is more of an operation factor (and normal for all base oils during service) and is often countered or overwhelmed by permanent shear and fuel dilution. Cheap base oils may oxidize and break-down quicker, but I don't think there's any evidence of oils we've seen oxidatively thicken in service (AMSOIL, Redline) produce sludge (which requires moisture) or varnish in the process, which is a more complex process involving breakdown and plating-out of deposits that can no longer be held in suspension. View attachment 101491

If you start with base oils with naturally higher VI and are using less VII, there's less shearing possible, so ultimately oxidative thickening can become the primary driver of viscosity change. While PAO is more resistant to thickening, it is not immune:
View attachment 101492
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To add ... here's a Machinery Lubrication article that breaks down the stages of oil oxidation in pretty good detail.

www.machinerylubrication.com

Identifying the Stages of Oil Oxidation

Lubricants age and alter chemically by a process called oxidation. In fact, oxidation is the primary way a lubricant degrades over time from normal service. It typically results in impaired chemical and physical properties of the base oil and additives. Understanding why a lubricant oxidizes is...
www.machinerylubrication.com www.machinerylubrication.com
 
OVERKILL said:
The last SDS I have for Redline white bottle was for their 5w-30, and it showed majority PAO (and remember, you still need DI package and VII):
Screen Shot 2018-10-25 at 7.20.20 PM.png
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Just wanted to point out that that's the MSDS from the rebranded Kendall they sell as Red Line Pro.
 
Sorry, correction, HERE is the SDS from the white bottle 5w-30 Redline (though, IIRC, they all had the same SDS):
1653608440418.png


Two different types of PAO, at less than 90%, lol.

Previous posted edited with the correct pic.
 
Could you explain what each of those values mean? I would like to know, but this is really confusing
 
OVERKILL said:
Sorry, correction, HERE is the SDS from the white bottle 5w-30 Redline (though, IIRC, they all had the same SDS):
View attachment 101509

Two different types of PAO, at less than 90%, lol.

Previous posted edited with the correct pic.
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Yeah, after 2017 or 2018 they obfuscated the MSDS even furthet. Suffice to say that their ester formula is majority PAO when it comes to motor oil, though according to Oilclub.ru, 5W-30 has somthing like ~18% POE content.

BMW Dom said:
Could you explain what each of those values mean? I would like to know, but this is really confusing
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An MSDS is supposed to be a safety document. Some oil blenders are more generous with theid descriptions for various feasons (free advertising for one), while others are downright cryptic. They are under no obligation whatsoever to divulge the actual contents and quantities. Only what's haxardous and the effects on humans and the environment. The numbers represent CAS numbers and there is a description of the chemical compound that the CAS number belongs to.
 
OVERKILL said:
I don't think that's accurate, based on what I've read about AN's. POE has a heavy impact on seal swell. AN's are far closer to neutral on seals (while still having some seal swell tendencies).

I'd highly recommend reading this paper from the STLE, which I shared in my thread on Dr. Rudnick:


Which features the following table:
View attachment 101508

Which notes that esters cause seal swell, while AN's have less impact on seals than esters.
Click to expand...
The STLE link on page 11 and summary on page 56 says AN has good seal swell properties. Thanks for your links… will take my time reading them.
 
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Bill_W said:
The STLE link on page 11 and summary on page 56 says AN has good seal swell properties. Thanks for your links… will take my time reading them.
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Yes, exactly, good seal swell, not excessive seal swell, lol. It's closer to neutral than esters, which means you can use more of it without creating a seal swell issue, which can improve solubility and varnish dissolving.
 
Do the new 2020 and up pentastar engines still have engine problems?
 
"Again, it all depends on the use circumstances. Those vehicles you mention may have adequate oil coolers and keep the oil temperatures down. You could run 0W-8 in a vehicle specifying 10W-40 if you kept the oil temperature of the 0W-8 down to where the viscosity was about equal to the 10W-40 at 275 F. It's all about oil temperature, and what the oil's viscosity is at those temperatures, because the viscosity between the moving parts does matter."

Interesting that I said exactly this once and was ravaged by many as being utterly false.

ali
 
As someone who's been in there and done that, I'll share my experience with you. Take it with a big slab of salt if you like.

My opinion, like others have mirrored here, is that oil will not fix an engine deficiency or design flaw. I can tell you that when I replaced my rocker rollers and lifters, they were revised part numbers. That tells me there was likely a design or manufacturing flaw identified with the old part number, and it was addressed in some way. Having taken my old rocker rollers out, I can say that some did have bearing wear, which caused additional drag on the camshafts. Luckily, my camshafts were still within spec, but if I neglected it, it would've almost certainly become worse and wiped my cam lobes.

Here's the part that might catch me some criticism. While I was in there, I uninstalled the known faulty OEM plastic oil cooler/filter assembly. I replaced it with a cast aluminum assembly and then installed a Baxter spin on oil filter adapter onto that. I never liked how the dry starts sounded on my 3.6 with the cartridge filter setup. I also didn't like the bypass built out of brittle plastic in the end cap, which is also known to fail. With a spin on oil filter, I get a silicone ADBV and I get a secondary one in the adapter itself. My startups sound better, but I'm waiting through this OCI to see if my oil ends up cleaner (i.e. less wear material) than it did stock. The intent with the stock oil filter setup is that the variable displacement pump has such a high PSI, that it can get oil up to the valvetrain before any damage occurs. I'm not so sure about that.
 
AEHaas said:
"Again, it all depends on the use circumstances. Those vehicles you mention may have adequate oil coolers and keep the oil temperatures down. You could run 0W-8 in a vehicle specifying 10W-40 if you kept the oil temperature of the 0W-8 down to where the viscosity was about equal to the 10W-40 at 275 F. It's all about oil temperature, and what the oil's viscosity is at those temperatures, because the viscosity between the moving parts does matter."
Click to expand...
If you're doing all that, then why not just use the 40-grade with an appropriate winter rating for your climate? Saves money and reduces mechanical complexity.
 
AEHaas said:
"Again, it all depends on the use circumstances. Those vehicles you mention may have adequate oil coolers and keep the oil temperatures down. You could run 0W-8 in a vehicle specifying 10W-40 if you kept the oil temperature of the 0W-8 down to where the viscosity was about equal to the 10W-40 at 275 F. It's all about oil temperature, and what the oil's viscosity is at those temperatures, because the viscosity between the moving parts does matter."

Interesting that I said exactly this once and was ravaged by many as being utterly false.

ali
Click to expand...
Yes, because HTFS is irrelevant. :rolleyes:
 
As higher grade oils have more internal resistance they heat up more in the bearing area. Whereas a 20 and 30 grade oil will have a different viscosity at 90C they may have the same viscosity when exiting the bearing as the thinner, 20 grade oil will heat up less:

Screen Shot 2022-06-23 at 4.09.48 PM.jpg
 
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