Flipping Oil Viscosity

Astro14

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I see some chatter here on bitog about failed motors that were using a heavier oil than specified, like a 20w50 when 5w30 or 0w20 was called for. That does seem odd. But, any fails from say using a modern 0w20 synth where a 20w50 was called for?
You joined yesterday.

To what chatter are you referring?
 
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In all seriousness...

Gary Allan used a custom 0W10 in a Jeep 2.5L with decent UOA results. The engine certainly did not blow up.
I've lost my oil after rolling my Wrangler over (2.5L as well) and had nothing but spare 20wt in my club's modern Wranglers and it didn't blow up.

Please post links to the chatter you heard so we can reference and comment.
 
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Years ago there was a thread where a poster used either 5W20 or 0W20 in a 20W50 spec car (maybe 70s or 80s vintage car), and the engine blew. It was so long ago that I don't remember the details about the thread.
 
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In all seriousness...

Gary Allan used a custom 0W10 in a Jeep 2.5L with decent UOA results. The engine certainly did not blow up.
I've lost my oil after rolling my Wrangler over (2.5L as well) and had nothing but spare 20wt in my club's modern Wranglers and it didn't blow up.

Please post links to the chatter you heard so we can reference and comment.
He's talking about the other way around ... using heavy oil in a light oil specification and the engine "blowing up". Words in Post #1: "... failed motors that were using a heavier oil than specified, like a 20w50 when 5w30 or 0w20 was called for."

I don't recall any threads on BITOG discussion such subject matter.
 
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Honda Shadow probably ain't a modern engine at all, at least not covering the field all too well. A modern engine may check (some) viscosity and figure it in for actuators, pumps, I don't know what. Or just suffer one or another way without ever taking notice. Or be fine with it. Or see it as extra care under unusual circumstances. Or combine some of above within a road trip... Likewise not all points of lubrication within an engine are created equal anyway.
So revisit the chatter and follow into the examples and details, try to find out what you're actually interested in. A 5W-30 could be a common CK-4 most people would accept or could be FA-4 infernal stuff within the same grade. So just don't forget to take it far enough, once you awoke your first interest in viscosities. Otherwise most answers can't help.
 
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Jimmy_Russels

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Honda Shadow probably ain't a modern engine at all, at least not covering the field all too well. A modern engine may check (some) viscosity and figure it in for actuators, pumps, I don't know what. Or just suffer one or another way without ever taking notice. Or be fine with it. Or see it as extra care under unusual circumstances. Or combine some of above within a road trip... Likewise not all points of lubrication within an engine are created equal anyway.
So revisit the chatter and follow into the examples and details, try to find out what you're actually interested in. A 5W-30 could be a common CK-4 most people would accept or could be FA-4 infernal stuff within the same grade. So just don't forget to take it far enough, once you awoke your first interest in viscosities. Otherwise most answers can't help.
But does it matter what engine it is? Now you thrown in semantics around the different types of engines. A old Honda engine that calls for a 20w50 vs a "modern" engine that calls for 20w50. Would it really matter what engine if they all called for 20w50 and the oil jug service rating met or exceeded engine requirements? What if it were 5w40 and you used a 0w20?
 

Jimmy_Russels

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Hey "Jimmy", are you going to answer Astro14's question above?
The chatter Q. Yeah, I am looking for it. Another user stated because the vehicle owner was using 20w50 the engine die early and they had to replace it. I am looking for that, but there are some many posts here on btog it's not so easy to find. Maybe that Astro14 can find it?
 
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The modern engine tends to expect the 0W-20. But you're right, you seem to articulate two problems at least. May I ask if – after so much chatter and reading up – you remained equally puzzled how any deviations in any direction could be unfortunate at all?
In this case I'd just give up on multigrades to avoid overthinking things and maximize deviations in directions. Engines that tend to get along with anything from 0W-20 to 20W-50 should be fine without the W.

The engine only matters if you want to know what you're talking about.
 
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The chatter Q. Yeah, I am looking for it. Another user stated because the vehicle owner was using 20w50 the engine die early and they had to replace it. I am looking for that, but there are some many posts here on btog it's not so easy to find. Maybe that Astro14 can find it?
No, you're the one who claims the chatter exists. How about you find it, "Jimmy"? Astro14 isn't your... well you know.
 
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The chatter Q. Yeah, I am looking for it. Another user stated because the vehicle owner was using 20w50 the engine die early and they had to replace it. I am looking for that, but there are some many posts here on btog it's not so easy to find. Maybe that Astro14 can find it?
I can't believe using 20W-50 in anything is going to "blow it up" unless some bonehead is using it in the winter, starts the engine and floors the engine to redline while the oil is still cold. Many motorcycles and high performance cars specify 20W-50 and if you look at the journal bearing clearances they are just as tight as vehicles calling for 0W-20 oil. So that tells me right there that using thicker oil in any engine under normal circumstances isn't going to "blow it up". Based on the science of tribology, a thicker oil actually provides more MOFT and therefore more wear protection.
 
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I can't believe using 20W-50 in anything is going to "blow it up" unless some bonehead is using it in the winter, starts the engine and floors the engine to redline while the oil is still cold. Many motorcycles and high performance cars specify 20W-50 and if you look at the journal bearing clearances they are just as tight as vehicles calling for 0W-20 oil. So that tells me right there that using thicker oil in any engine under normal circumstances isn't going to "blow it up".
Now you can re-ask the question you had for Barry in the other thread. I think you might want to do it quickly though.
 
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Which type motor?

Gas, diesel, Cold Fusion or Mr. Fusion?

It makes a difference if "nucular" energy was involved because of the effect on the molecular bonds oil cooling the flux capacitor
1.21 JigaWatts or GigaWatts?

 
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I can't believe using 20W-50 in anything is going to "blow it up" unless some bonehead is using it in the winter, starts the engine and floors the engine to redline while the oil is still cold. Many motorcycles and high performance cars specify 20W-50 and if you look at the journal bearing clearances they are just as tight as vehicles calling for 0W-20 oil. So that tells me right there that using thicker oil in any engine under normal circumstances isn't going to "blow it up". Based on the science of tribology, a thicker oil actually provides more MOFT and therefore more wear protection.
Yup, the only time a 20w-50 is potentially going to "blow something up" is if we are talking about an oil pump driveshaft failure or it's -30 and it simply can't pump.
 
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