Engine wear comparison via Blackstone labs of 5W-30 versus 5W-20.

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I would also go 5k. Today’s cheapest oils would last in those driving conditions with room to spare. 5w-30 would be my choice as well. No science behind it, just seems my engines “like” it better. They seem to run slightly quieter and mileage is really not affected.
 
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One star thread.

Likely won’t matter one bit. You’re using top tier oil and filters for 4k and given your future driving pattern, you’re dumping good oil and filters way prematurely.

You bought a Honda, not a yugo. You likely bought that Honda because of the known quality of the brand. Honda didn’t get its name from people over-maintaining their cars. They got it because they build good, reliable automobiles that can likely take lots of abuse and still last and last. Use what the oil cap says and sleep well at night. Now enjoy your reliable vehicle. Don’t work for your van, let the van work for you.
 

Bill7

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I'm very close to making the decision to switch permanently from 5W-20 to 5W-30.

Please take the next statement with a grain of salt. It's not based on any scientific data, just a feeling.
So many cars end up consuming a ton of oil and can't pass emissions tests and reach end of life at 200k miles.
At that point, people don't want to keep them if they have to add a quart of oil every 500 miles.
Wonder if everything else being equal, if they had used 5W-30 since new (instead of 20 weight oils), if they would be going strong for another 100,000 miles to 300,000 total.
 
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Bill7, PLEASE do this test and let us know the results!

It would answer the question and help quash the bickering about this topic.

Anything other than a UOA is guessing, but my guess is that the -30 may have slightly lower wear. Since you are using the same oil/filter combo always, that removes a variable.

(Have to throw in there that to me, 4,000 is a short interval with that oil and usage, but I respect your decision)

Looking forward to the results!
 
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Wonder if everything else being equal, if they had used 5W-30 since new (instead of 20 weight oils), if they would be going strong for another 100,000 miles to 300,000 total.
That's the sort of thing that needs researched, but I don't see it happening so we just keep saying things like "I switched to 5w30 and everything's fine" and vice versa, which is worthless anectodal information that tells us zero. The smarter guys seem to agree that more HTHS decreases wear so I've got that at the top of my "I can't prove it but it makes sense and those dudes all said it" list. 😁
 
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Oil change with PUP and Ultra is what... $40? Every 4k?

300,000/4k = 75 oil changes x $40 = $3000

If it is all highway, double your interval to 8k, and change the filter every second time. Now the total cost is more like $1100 and it won't make a lick of difference in engine longevity. 10k interval and filter every second, more like $800. This doesn't even take into account any time you use out of your life to do all those unnecessary oil changes.
 
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Bill7, PLEASE do this test and let us know the results!

It would answer the question and help quash the bickering about this topic.

Anything other than a UOA is guessing, but my guess is that the -30 may have slightly lower wear. Since you are using the same oil/filter combo always, that removes a variable.
Looking forward to the results!
No bickering here at all. A UOA is not the tool to determine comparative wear between oils.
 
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I'm very close to making the decision to switch permanently from 5W-20 to 5W-30.

Please take the next statement with a grain of salt. It's not based on any scientific data, just a feeling.
So many cars end up consuming a ton of oil and can't pass emissions tests and reach end of life at 200k miles.
At that point, people don't want to keep them if they have to add a quart of oil every 500 miles.
Wonder if everything else being equal, if they had used 5W-30 since new (instead of 20 weight oils), if they would be going strong for another 100,000 miles to 300,000 total.
What OCI was used in those miles? What were the operating conditions? What oil and air filters were used? What is the specific engine design?
 
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No oil of a higher HT/HS than what is recommended in the manual will damage an engine. Thicker oils help prevent wear, not cause it.

There are some exceptions to that if gone extreme enough. I've seen spalled rod bearings as a result of bearing fatigue caused by excessive heat from excessive hydrodynamic lubrication from excessive oil viscosity for the clearance.

In some cases where an engine has worn rings, a higher HTHS oil can facilitate more oil transport past the rings into the chamber causing an increase in oil consumption rather than a decrease.
 
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How about an SAE grade then? Is this a concern in warm Australia where some vehicles have a recommendation for a 60-grade oil?

Either way it’s not going to happen here with the small difference between a 20 and a 30-grade is it?
 
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With the long trips you are an ideal candidate for 10,000 mi oci on Synthetic with 20,000 mi changes on a Premium Filter.(Like an Ultraguard)

If you want to run 6,000 mi OCi with any properly rated conventional and 12,000 mi changes on a moderately priced filter (Like an Extraguard) you can.

I've never seen any study that supports what you are trying to accomplish. What I've seen suggest that the longer drains (as long as not excessive) with a synthetic are the most effective way to go and short intervals with a synthetic give no benefits for typical vehicles.

If you are going to do analysis the things you really need to keep an eye out for are air leaks (dirt) and coolant in the oil. These are far more important to longevity.
 
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