Does 5W-30 REALLY protect better than 5W-20?

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Oil keeps the parts separated. Thicker oil keeps the parts seperated more. If the 20 keeps the parts speperated through out the most severe operating conditions well,, the parts are separated . Then there is the base oil blend, viscosity improvers and stuff a pro needs to explain.
 
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Oil keeps the parts separated. Thicker oil keeps the parts seperated more. If the 20 keeps the parts speperated through out the most severe operating conditions well,, the parts are separated .
"If" and "throughout" are the key words. Give "if" and "throughout" more headroom by going thicker than 20. :D
 
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They may also recommend a specific brand of oil. Was the engine designed around that brand as well?

Typically, no. But if it's a BMW, they will run your oil through a Oil Sniffalation 3000 to determine if you used Castrol acquired from the dealer.

And if you didn't, that is why the German Engin-froiden-neering failed.

These are just facts. I just state the facts.
 
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Typically, no. But if it's a BMW, they will run your oil through a Oil Sniffalation 3000 to determine if you used Castrol acquired from the dealer.

And if you didn't, that is why the German Engin-froiden-neering failed.

These are just facts. I just state the facts.
Actually, BMW requires oils with their own approvals, not specific brands. I guess you just stated a non-fact. But who’s to be surprised...
 
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Typically, no. But if it's a BMW, they will run your oil through a Oil Sniffalation 3000 to determine if you used Castrol acquired from the dealer.

And if you didn't, that is why the German Engin-froiden-neering failed.

These are just facts. I just state the facts.


Sounds like Hong Kong Phooey to me.
 
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Oil keeps the parts separated. Thicker oil keeps the parts seperated more.


Someone will have to explain this part to me. Can internal engine parts actually be separated more? I thought it was about film strength?
 
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Someone will have to explain this part to me. Can internal engine parts actually be separated more? I thought it was about film strength?
No, but they can be separated less with a lower MOFT. So you’re right, it’s about “film strength”.
 
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No, but they can be separated less with a lower MOFT. So you’re right, it’s about “film strength”.


I think the term “separated” is being used improperly in this respect. That’s what is making me curious. Of course we are talking about very minute measurements here.
 
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I think the term “separated” is being used improperly in this respect. That’s what is making me curious. Of course we are talking about very minute measurements here.
I always start from the extremes. Two identical engines, one running with distilled water as lubricant, the other with some 70W racing oil. We all know which one we would pick as our daily driver. The practical “sweet spot” is in between, however. That will be determined by “countless” hours of engineering work, millions of dollars, and - sadly - by politics.
 
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Someone will have to explain this part to me. Can internal engine parts actually be separated more? I thought it was about film strength?
No, but they can be separated less with a lower MOFT. So you’re right, it’s about “film strength”.
Basic tribology shows that higher viscosity results in more film thickness/MOFT between moving parts - been that way since the beginning of time. And there is a distinct difference between "film thickness" (MOFT) and "film strength".

 

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"If" and "throughout" are the key words. Give "if" and "throughout" more headroom by going thicker than 20. :D
Let's just call is separated because with out using what ever term we want to call proper oil keeps the parts separated. Liquid ball bearings and or intelligent molecules.
 
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