Oil Recommendations for Highest Wear Protection

[tessaseveride]

Hey. I recently purchased a 2023 Subaru BRZ (FA24) and the owner's manual calls for 0W-20 API SN/SP Resource Conserving or ILSAC GF-5/6A. After some research, it seems like the recommendation for 0W-20 is more for CAFE and EPA satisfaction, rather than engine performance and longevity. I'm sure using 5W-30 wouldn't harm anything outside of fuel efficiency (which is what I did in my Miata anyways when it called for 5W-20), however while researching oils, I went down the HTHS rabbit hole and now I'm looking at possibly using a Euro oil for the higher viscosity.

Does HTHS above 2.9 in the API/ILSAC specs for 5W-30 actually have value, or is it just additional headroom for when the oil shears? Seems like all the Euro oils have HTHS or 3.5 or higher for their manufacturer approvals. Also, I understand that most of the Euro specs are more stringent than API and ILSAC requirements, so there shouldn't be any compatibility issues with something like Pennzoil Euro L 5W-30 in my engine, correct? No issue with it being a mid-SAPs oil or that it's missing moly, tungsten, or titanium? That oil specifically has SN approval (not Resource Conserving), Dexos 2, and a few Euro specs. Any oil recommendations that you guys would recommend? I'd like something off the shelf if possible.

For context, the vehicle is in a southern state, warm/hot climate 10 months out of the year, will be used as a daily driver (a lot of short tripping, 5 miles a day commute both ways), and HPDE events or canyon carving on the weekends. I don't care about the factory warranty. If it really comes down to needing to use it, I will pursue legal action if the Subaru attempts to "void" my warranty. The manufacturer isn't going to be there to hold my hand if the engine blows a day late or a mile over. Any guidance would be greatly appreciated. Thanks.

 

[kschachn]

I'd say you have it pretty well figured out. What is your question again?

Oils don't shear by the way, VII do. Which is actually pretty rare. Fuel dilution is the most common cause of a viscosity deviation.

 

[tessaseveride]

I'd say you have it pretty well figured out. What is your question again?

Oils don't shear by the way, VII do. Which is actually pretty rare. Fuel dilution is the most common cause of a viscosity deviation.

Does having higher HTHS than what regular 5W-30 API/ILSAC approved oil actually matter? Any issue with using mid-SAPs oils? How about oils that seem to omit moly, titanium, and tungsten in their formulations? I'm not familiar with what those 3 additives exactly protect against, so I'm not sure if it's something I should be looking into VOAs for.

 

[atikovi]

My understand is that car manufacturers oil recommendations in the U.S. are fuel economy driven, not engine durability driven. That makes sense as manufacturers have to appease the EPA rating their cars are given, plus, they have planned obsolescence in mind and don't want your engine to last 300,000 or 400,000 miles. The 0W20 spec your U.S. car has might be 5W30 in the rest of the world.

 

[kschachn]

Film thickness (as represented by the HT/HS) prevents wear, yes.

As for specific elements in a spectrographic analysis and how their concentration, absence, or presence affects the future performance of a formulated motor oil, well that’s way beyond my capability. And I would say it’s beyond the capability of almost everyone on here. Such a determination requires expensive and complicated tests. What you’re mentioning in your post are elements not additives.

 

[buster]

There are a lot of choices. If you want an approved oil - any of the top tier major formulations (M1/Pennzoil/Castrol) would be good. Mobil 1 ESP is highly regarded. If you want ultra-premium booshie non-approved - HPL, Amsoil and Redline.

 

[tessaseveride]

My understand is that car manufacturers oil recommendations in the U.S. are fuel economy driven, not engine durability driven. That makes sense as manufacturers have to appease the EPA rating their cars are given, plus, they have planned obsolescence in mind and don't want your engine to last 300,000 or 400,000 miles. The 0W20 spec your U.S. car has might be 5W30 in the rest of the world.

Seems that way. I found the Australian manual recommends 5W-30 and does not mention 0W-20 at all. I will search for a thick 5W-30 oil. Thanks.

 

[tessaseveride]

Film thickness (as represented by the HT/HS) prevents wear, yes.

As for specific elements in a spectrographic analysis and how their concentration, absence, or presence affects the future performance of a formulated motor oil, well that’s way beyond my capability. And I would say it’s beyond the capability of almost everyone on here. Such a determination requires expensive and complicated tests. What you’re mentioning in your post are elements not additives.

Gotcha. I'll try to do more research into what each individual additive does in oil formulations. I specified additives because I assumed they weren't actually individual elements in the oil, but compounds like molybdenum disulfide or tungsten disulfide. Is that incorrect?

 

[JRHAWK9]

May want to also look into Mobil1 ESP 5w30. It's one I am considering for my FB25 in my '21 Crosstrek.

 

[tessaseveride]

May want to also look into Mobil1 ESP 5w30. It's one I am considering for my FB25 in my '21 Crosstrek.

I'll look into it. Thank you!

 

[radiometer]

May want to also look into Mobil1 ESP 5w30. It's one I am considering for my FB25 in my '21 Crosstrek.

Mobil 1 ESP 5W-30 would be a great choice. I use it myself.

 

[tessaseveride]

Could anyone educate me on low, mid, and high saps formulations? Advantages, disadvantages, etc? Seems like it's more of a deciding factor for diesel vehicles that have filters that can get clogged and less of a factor for the gasoline passenger car market.

 

[BMWTurboDzl]

Hey. I recently purchased a 2023 Subaru BRZ (FA24) and the owner's manual calls for 0W-20 API SN/SP Resource Conserving or ILSAC GF-5/6A. After some research, it seems like the recommendation for 0W-20 is more for CAFE and EPA satisfaction, rather than engine performance and longevity. I'm sure using 5W-30 wouldn't harm anything outside of fuel efficiency (which is what I did in my Miata anyways when it called for 5W-20), however while researching oils, I went down the HTHS rabbit hole and now I'm looking at possibly using a Euro oil for the higher viscosity.

Does HTHS above 2.9 in the API/ILSAC specs for 5W-30 actually have value, or is it just additional headroom for when the oil shears? Seems like all the Euro oils have HTHS or 3.5 or higher for their manufacturer approvals. Also, I understand that most of the Euro specs are more stringent than API and ILSAC requirements, so there shouldn't be any compatibility issues with something like Pennzoil Euro L 5W-30 in my engine, correct? No issue with it being a mid-SAPs oil or that it's missing moly, tungsten, or titanium? That oil specifically has SN approval (not Resource Conserving), Dexos 2, and a few Euro specs. Any oil recommendations that you guys would recommend? I'd like something off the shelf if possible.

For context, the vehicle is in a southern state, warm/hot climate 10 months out of the year, will be used as a daily driver (a lot of short tripping, 5 miles a day commute both ways), and HPDE events or canyon carving on the weekends. I don't care about the factory warranty. If it really comes down to needing to use it, I will pursue legal action if the Subaru attempts to "void" my warranty. The manufacturer isn't going to be there to hold my hand if the engine blows a day late or a mile over. Any guidance would be greatly appreciated. Thanks.

Oil recommendations are based on availability/cost, operating parameters, fuel efficiency, and emissions.

Euro oils use HTHS and emissions compatibility to delineate various categories. 30w oils fall under 2 categories (HTHS 3.5 or higher, and 2.9 to 3.5)

BTW.. all the Euros have moved to 20 weight oils so you can take that for what it's worth. I'm talking engines which make twice as much power as your BRZ.

 

[tessaseveride]

BTW.. all the Euros have moved to 20 weight oils so you can take that for what it's worth. I'm talking engines which make twice as much power as your BRZ.

That's fine, but the recommended oil for my vehicle in most countries outside of the US is 5W-30, which means the 0W-20 recommendation in the US is strictly for politics. I don't believe you can base weight recommendations based on what some other irrelevant engine uses. Most race cars are above 500 hp and most commonly use 10W-60, that doesn't mean it would be ideal for every other engine out there.

Euro oils use HTHS and emissions compatibility to delineate various categories. 30w oils fall under 2 categories (HTHS 3.5 or higher, and 2.9 to 3.5)

Are you aware of any significant difference in wear protection between the two categories?

 

[JavierH19]

Pick any sp rated euro oil and sleep well.

 

[BMWTurboDzl]

That's fine, but the recommended oil for my vehicle in most countries outside of the US is 5W-30, which means the 0W-20 recommendation in the US is strictly for politics. I don't believe you can base weight recommendations based on what some other irrelevant engine uses. Most race cars are above 500 hp and use 10W-60, that doesn't mean it would be ideal for every other engine out there.

No it's not just politics. It's that 20w oils are ridiculously cheap in the US and it helps with fleetwide CAFE and no autobahn. There are race cars which use 0w5, 5w20, 10w30, 10w50, etc.

Are you aware of any significant difference in wear protection between the two categories?

No. Is there a non-significant difference? Perhaps but there are other variables such has size/location of an oil cooler which also must be factored in. Sure the higher HTHS euro oil will give you more headroom. Any 30w SP should be fine but we're all guessing here. If you want "the best" then buy from one of the majors (Mobil 1, Castrol, Shell) or go boutique (HPL, Redline, Amsoil, etc).

 

[tessaseveride]

There are race cars which use 0w5, 5w20, 10w30, 10w50, etc.

That's my point. You can't pick a specific grade out of an irrelevant engine and deem it acceptable for everything else.

I appreciate your help with the HTHS clarification. I'll look into HTHS >3.5 for my needs.

 

[sk_pete]

Does having higher HTHS than what regular 5W-30 API/ILSAC approved oil actually matter?

psa(stelantis) oil norm 0w30/5w30 changed from 2,6hths to 2,9 lately.... guess why...
long oci, d.i. , etc will make safety margin too thin
i guess saving few extra grams co2 during the year was not worth it.
other automakers think the situation is not that bad, but the day after warranty expires you´re on your own

 

[Astro14]

Does having higher HTHS than what regular 5W-30 API/ILSAC approved oil actually matter? Any issue with using mid-SAPs oils? How about oils that seem to omit moly, titanium, and tungsten in their formulations? I'm not familiar with what those 3 additives exactly protect against, so I'm not sure if it's something I should be looking into VOAs for.

Those three aren’t additives. Any more than bolts are cars.

Those are elements. From which additives are made.

Elemental analysis tells you very little.

Approvals and certifications tell you a lot.

 

[tessaseveride]

Those three aren’t additives. Any more than bolts are cars.

Those are elements. From which additives are made.

Elemental analysis tells you very little.

Approvals and certifications tell you a lot.

My mistake. I was looking at them as compounds being added, therefor "additives". Thank you for educating me.