Oil Recommendations for Highest Wear Protection

[Revving2Redline]

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.

Well Redline high performance in the white bottles can be had in 0w-20 or 5W20 and their hths is 2.9 and I believe 3.0

 

[MacManus99]

I personally ran 0w40 euro oils in my FA20 powered FRS with good results and used oil analysis.

The car was my daily driver, but saw fairly frequent autocross use and some track use. Daily use consisted of waiting for oil temp to come up, and then drive it like I stole it (within reason). Oil temps reached 250+ in autocross use. I kept a pretty short change interval, and the UOA I was getting came back good, so I didn't change anything.

I also ran one summer using a 15w40 diesel motor oil, good results with that as well. The euro oils that I used carried A40 and MB229.5 approvals, among others. God knows what approvals the HDEO had.

 

[tessaseveride]

I personally ran 0w40 euro oils in my FA20 powered FRS with good results and used oil analysis.

The car was my daily driver, but saw fairly frequent autocross use and some track use. Daily use consisted of waiting for oil temp to come up, and then drive it like I stole it (within reason). Oil temps reached 250+ in autocross use. I kept a pretty short change interval, and the UOA I was getting came back good, so I didn't change anything.

I also ran one summer using a 15w40 diesel motor oil, good results with that as well. The euro oils that I used carried A40 and MB229.5 approvals, among others. God knows what approvals the HDEO had.

That's awesome. I'm the same way with my cars. Let it come up in temp a bit and drive it like I stole it. I've also always kept a short change interval, around 3k miles or so. I'm starting to lean towards Euro spec thin xW-40 or xW-30 after what I've read and researched. I appreciate your input. Pennzoil Platinum Euro 5W-40 looks interesting and is easily accessible where I live. I may also try Euro L 5W-30 or Mobil1 ESP. Still researching whether or not low, mid, or high saps formulations makes a difference outside of potentially clogging cats.

 

[Krieg]

High Performance Lubricants or Mobil 1. There are other good motor oils too!

 

[Bill7]

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.

You and I think alike. Mobil 1 ESP 5W-30 Acea C3 and passes the latest very tough MB 229.52 spec. It has HTHS = 3.5.
I would stay away from the Acea A3/B4 Euro oils, as they have too much phosphorus and could harm your catalytic converter.

 

[MacManus99]

That's awesome. I'm the same way with my cars. Let it come up in temp a bit and drive it like I stole it. I've also always kept a short change interval, around 3k miles or so. I'm starting to lean towards Euro spec thin xW-40 or xW-30 after what I've read and researched. I appreciate your input. Pennzoil Platinum Euro 5W-40 looks interesting and is easily accessible where I live. I may also try Euro L 5W-30 or Mobil1 ESP. Still researching whether or not low, mid, or high saps formulations makes a difference outside of potentially clogging cats.

I agree and would encourage your use of Euro oils. My knowledge of SAPS is limited, but I don't think it is as much of an issue on your engine because of the D-4S injection. I don't think poisoning your cat is much an issue unless your engine is eating a significant amount of oil, in which case you likely have bigger problems than a converter. I had a stock cat on mine and mostly used Mobil 1 0w40 full SAPS oil. No issues at 70k miles. That said, I wouldn't hesitate to run a C3 oil either. Any Euro oil should be more than up to the task, regardless of SAPS levels.

 

[JRHAWK9]

Mobil 1 ESP 5W-30 Acea C3 and passes the latest very tough MB 229.52 spec. It has HTHS = 3.5

What's strange to me is that it's cheaper here than the Mobil 1 EP 5w30 is.

 

[Zee09]

What oil filter are you going to use?

 

[Delta]

I run 5w30 in my 2.5L Subaru. Whatever on sale synthetic I can get, this time it was Valvoline. Also run a Wix filter that has the correct bypass pressure for Subaru's.

Even the dealer thought it was a good idea over the 5w30 (long story of how it wound up there for an oil change with my stuff), which I thought was strange.

 

[tessaseveride]

What oil filter are you going to use?

Tokyo Roki, whether that be the Made in Japan Subaru OEM ones or equivalent (Mazda at the moment).

 

[tessaseveride]

I agree and would encourage your use of Euro oils. My knowledge of SAPS is limited, but I don't think it is as much of an issue on your engine because of the D-4S injection. I don't think poisoning your cat is much an issue unless your engine is eating a significant amount of oil, in which case you likely have bigger problems than a converter. I had a stock cat on mine and mostly used Mobil 1 0w40 full SAPS oil. No issues at 70k miles. That said, I wouldn't hesitate to run a C3 oil either. Any Euro oil should be more than up to the task, regardless of SAPS levels.

Makes sense since the port injection will wash the valves. I feel confident going with a Euro oil now. Thank you! And I guess even if my cat gets clogged, it's just an excuse to buy an upgraded header.

 

[kschachn]

Makes sense since the port injection will wash the valves. I feel confident going with a Euro oil now. Thank you! And I guess even if my cat gets clogged, it's just an excuse to buy an upgraded header.

It won’t get clogged. If you have (very) excessive oil consumption the phosphorus will passivate or poison the catalyst surface. But that is in the neighborhood of 1 quart in about 500 miles.

 

[Mekks]

Pick any sp rated euro oil and sleep well.

Forgive my stupidity, but what euro oils are SP rated? I have looked and most seem to carry SN omly but its been min.

 

[chainblu]

Since you're convinced thicker is better, I wouldn't 'wuss' around with a 30 grade. 0/5w-40 should serve you well.

 

[chris719]

Forgive my stupidity, but what euro oils are SP rated? I have looked and most seem to carry SN omly but its been min.

Mostly a few xW-40s because there are no restrictions on phosphorus content for oils > 30. Pennzoil Platinum Euro 5w-40 is one example. For thinner oils they would have to be low SAPS versions.

 

[tessaseveride]

Forgive my stupidity, but what euro oils are SP rated? I have looked and most seem to carry SN omly but its been min.

Mobil 1 ESP 5W-30 is also SP rated according to their website.

 

[kschachn]

Since you're convinced thicker is better, I wouldn't 'wuss' around with a 30 grade. 0/5w-40 should serve you well.

It’s more about the HT/HS than the grade.

 

[JRHAWK9]

Mobil 1 ESP 5W-30 is also SP rated according to their website.

I just picked up a 5qt jug and it only states SN on it. I know what you are saying though, as Mobil 1 states it is SP on their site/PDF.

 

[Bill7]

It’s more about the HT/HS than the grade.

Exactly. For those who haven't done so already, try googling this: HTHS wear graph

See how engine wear goes up exponentially when HTHS gets less than 2.6 (as when 20 weight oil sheers and get's thinner as it ages during a normal oil change interval).
HTHS = 3.5 is optimal.

Since I couldn't find any oils with HTHS = 3.5 that are also high mileage oils that treat engine seals, my best compromise is Pennzoil Platinum Full Synthetic High Mileage 5W-30 with Kinematic Viscosity of 11.4 @ 100C (which is on the thicker end of the spectrum for 5W-30's). It might indicate a HTHS of 3.2 (unknown since Pennzoil doesn't publish HTHS #'s).

I honestly don't feel comfortable using 20 weight or thinner oils in any vehicle (regardless of what the CAFE automobile company tax avoidance owners' manuals say), so I only run HTHS >= 3.2 oils in any vehicles I own or will own. To me, having an engine last 300k miles with no oil consumption (wear) or oil leaks is more important that saving 0.1% in gasoline.

When I used to use 20 weight oils, and my heavily loaded 8 passengers + luggage minivan was going up mountain inclines, with temp gauge on dashboard climbing, I used to worry - hey, did I just cause engine wear with this trip. But with a higher HTHS >= 3.2 oil, I never have that concern anymore.

Some other maintenance I do is:
OCI = 4k miles.
Drain/fill ATF fluid every 15k miles.
Change PCV valve and tube (with OEM parts) every 30k miles.
Only use Fram Ultra Oil + Air filters (Efficiency of both = 99%+ @ 20 microns).

 

[JRHAWK9]

O man, I just ran across this gem.