First sample, 2019 Subaru Ascent, 7300 miles HPL Premium Plus 0w30

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So I picked up this Ascent a couple months back and within 150 miles or so I drained it and put HPL Premium Plus 0w30 and a Fram Endurance 7317 on. This is my wife’s vehicle, and she is probably 65% short-trip city and 35% highway as a guess.

When I pulled this in-service sample, I went ahead and changed the air filter to a Fram Ultra panel filter, and it’s a good thing. Whoever installed the last MIC panel didn’t take care and had folded over a couple pleats and wedged them in between the box, leaving a small gap. This obviously showed up in the sample, at 47ppm silicon which should come down significantly next sample. Also, due to the short tripping, fuel was a little high at 6.3%.

I’ll be swapping in HPL SuperCar 0w30 this week, but the car’s now just shy of 10k due to waiting on sample results and my wife drove her friend to Cleveland and back twice. It’s time to come out, but I’m not too concerned. Iron is <1ppm/1k, copper very low compared to many Subaru/oil cooler UOAs, and viscosity was still above what an Ascent would normally be since I chose a 30 grade, which seems to be a wise move if you’re going >5k OCIs. Oxidation was very low compared to VOA, and BTW… moly lovers- 740ppm!

All in all, not a bad initial run I think, even with the two items of note. Seems most “discerning” Ascent owners are in the 3500-4500 mile OCIs, so again we’re at the break-even or slight advantage to the more expensive, double-plus distance oil. Will see if I can “modify” the operator’s behaviors to get fuel below 5%.

Thoughts?

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TBN was still 9.44!

Dave has said SuperCar is their best oil, but does not have as high a starting TBN as some of the PCEO offerings, so I will probably sample that at 6k and see where to go.
 
6.3% fuel is definitely high and something to keep monitoring. I'm assuming this vehicle does a lot of cold idling which is contributing to the fuel dilution. But otherwise appears to have handled the fuel dilution quite well.
 
6.3% fuel is definitely high and something to keep monitoring. I'm assuming this vehicle does a lot of cold idling which is contributing to the fuel dilution. But otherwise appears to have handled the fuel dilution quite well.
Yeah, she does idle it for about 30 seconds before driving away first thing in the morning (something she never did before) but I honestly think this is more sitting in parking lots with the AC running. Subaru does not do any stop/start BS on this, and the FA series is pretty well known for fuel dilution even on track-only machines.

I had already ordered the SuperCar since I planned on running the same oil in my truck and the Ascent, but now seeing the fuel% I may go back to the No VII Euro 5w30 in both vehicles based on how the Ascent does on SC.

I agree that above 5% fuel is worth reacting to, but as you noted the viscosity is a little low but otherwise appears completely capable at this point… the No VII Euro seems to thicken a little more quickly than Premium Plus, and this would counteract the viscosity portion of the concerns- in my truck with <1% dilution it thickened from 11.2cSt to 12.7cSt over 14,400 miles, which is fine as long as you’re aware of what’s going on.

I’d much rather have the oil thicken faster than dilution thins it. Anyways, just posted this up as we don’t normally see Ascent UOAs nor Premium Plus.

TL;DR: based on Premium Plus results & @High Performance Lubricants input in this instance, I will sample the SuperCar 0w30 at 6k and react as needed, but if/when I move to No VII Euro 5w30 I will sample at 10k based on my 16k experience in my 3.5EB.

@Jack_Kieran this is WearCheck in NC. Highly recommend them. Cost is about $35 but this sample delivered Friday afternoon and results were posted late Monday.

You can order the WearCheck kits from Mary Jane (HPL’s superstar CSR) @ (815) 932-3288; can’t remember if the BITOG15 code works on this or not. Either way, at $35 with gas chromatography for fuel % vs some of the others, plus the very quick turnaround, it’s a great deal!
 
No makeup. Oil level has stayed just above the upper mark, so considering the fuel % I would guess it used maybe 6 ounces over nearly 10k miles. Based on what I can see in the catch can on my truck, it’s most likely the lighter ends of the oil with a low level of additives carried along going thru the PCV system.

Once I finally figured out the dumb way Subaru hides the oil temp gauge, during city driving the temps stay about 198*F, and at a constant 72 on the highway regardless of ambient they stay right at 205F. Highest I’ve seen was 209F, and that was after it had been on the highway and I took about a 1/4 mile long on-ramp at WOT.

Maybe if I tracked the Ascent like @TiGeo does (albeit much slower) I could get some of the fuel to boil off 🤣
Very nice. Any makeup oil added?
 
This is a case where I think the viscosity bump actually makes sense. Not due to fear of 0w20 being inadequate but to hedge your bets against inevitable fuel dilution and thinning of the oil. Impressive UOA. I should have bought some HPL during the 4th of July sale!
 
I'm heading down to VA tomorrow night and I want to see how high the temps get in my 18 Legacy which isn't GDI. I think I have seen about 229 as the high before but I didn't make note.
 
Oh the horrors of fuel dilution.
:unsure:
I was way more concerned when I first opened the report and saw the 47ppm silicon- definitely flag worthy! I’m not really sure how between the fuel and silicon the numbers weren’t higher.

I give credit to HPL and Fram Endurance at this point. Kinda hard not to with everything else being as good as it was. It’s no 30k OCI, but it’s definitely higher mileage than the universal average..
 
Nice report, It farther confirms my choice for oil(viscosity) in my 2024 Outback XT with the FA24DIT.
I expect scary fuel dilution this winter I might even send in a UOA to check.
 
Nice report, It farther confirms my choice for oil(viscosity) in my 2024 Outback XT with the FA24DIT.
I expect scary fuel dilution this winter I might even send in a UOA to check.
Yes, without the 30 grade “cushion” and knowing TBN would be very high on the Premium Plus, I think Subaru’s 6k OCI recommendation is as far as I would push any shelf oil on this engine.

Despite the fuel and Si, the engine wear was very reasonable, all things considered.
Yes, I obviously didn’t notice the air box issue until I went to change the old filter, and fuel was going to be a known issue, but I’m still really pleased with the result knowing this is a majority “severe service” use especially going this distance on the initial UOA for this engine.

I purposely let it go longer because I’ve learned that if the sample interval is too short, virtually all oils will appear similar. Thx for the feedback!
 
Wow, that's some of the highest fuel dilution that I've seen in a Subaru DIT. Several years ago, there was someone on the Forester forum that got their dealer to look into a fuel injector issue based on high fuel on their 2.0 DIT Forester. I believe his was over 6% as well. Turned out the dealer was able to confirm that there was a leaky fuel injector and it was replaced under warranty. I think it's rare that a dealer will investigate anything based on a UOA though.

Are you actually allowed to use the SuperCar oil in an Ascent? I think you'd at least need to get a Cobb reflash for it. 😁

Thanks for sharing!
 
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Are you actually allowed to use the SuperCar oil in an Ascent? I think you'd at least need to get a Cobb reflash for it. 😁

Thanks for sharing!
My Ascent identifies as a SuperCar 🤣

Did you hear about how they actually test for a leaky injector? I’m on the far side of 65k so it will all be my nickel for diagnosis and repair if it’s an issue.
 
I don't recall what they did, but it might be in this discussion.

Check the uoa in post 41.

I've contacted my Subaru dealer about the results, the service manager is sending my reports in to SOC to see if they have anything to add, and they're asking me to bring in the car to them for my next oil change so that they can add these to my service records, just in case anything happens in the future.
I don't see a reply so maybe I got it mixed up with another one.

Check comments here from justinjs
https://www.subaruforester.org/thre...nside-cabin-when-parked.606521/page-3#replies

"I didn't get to talk to the Tech, the paperwork just states that "Tech found Fuel Injectors Leaking". When I took my car to the other dealership they claimed they checked the whole fuel system as well."

Maybe the Subaru Select Service Monitor?
 
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