Valvoline R&P 5W-30, 4K OCI, 2025 Subaru Forester
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I don't like that KV100. Even when you factor the fuel dilution, it's still out of grade.
Otherwise, it's a good report for a new engine.
Otherwise, it's a good report for a new engine.
Unless there may actually be a leak on air intake. Strange things happen at times even on a new build. Loose clamp? filter MIA or ripped? seal pinched? It happens.
For a light duty application, does it matter?
I've noticed with VRP UOA's, wear metal control looks solid. Viscosity also tends to drop, although it may not matter for the everyday car.
Are you going to sample again to trend the SI? Looks good to me eyes.
Are you going to sample again to trend the SI? Looks good to me eyes.
Subaru’s tend to drop a grade in my experience. One of the reasons I run a 30 grade, the other is oil temps get into the 230’s on the N/A 2.5’s.
The silicon is probably from RTV used in assembly, if it's that new.
With the Oil Temperature being 230 that you are seeing, do you know where the temp reading is taken from? I hope that oil temp is not being taken from the Oil Pan!
The oil temperature sensor on a Subaru can vary slightly depending on the model and engine type, but here are the most common locations:
Typical Sensor Locations
- Front oil galley plug: Often found under the alternator, this is a popular spot for both OEM and aftermarket sensors. It provides accurate readings since it’s close to the oil flow to critical engine components2.
- Rear oil galley plug: Located near the turbo on turbocharged models. This area tends to be hotter and is favored for performance monitoring.
- Oil drain plug: Some Subaru models use this location for OEM sensors, though it may read slightly lower due to oil pooling and cooling effects.
- Sandwich adapter: Installed between the oil filter and engine block, this allows for easy sensor installation without modifying engine components.
Do we know if the previous oil was a 20 grade and carryover contributed to the thinning?
Factory fill was 0W-16.
There ya go. No need to flag the viscosity until after two runs of the same oil, or at least oils with a similar starting viscosity.
Previous was the factory 0W16
Looks good to me. No oxidation at all. Viscosity drop is prob a combination of fuel and previous use of 0w16. But API SP 5w30's with HT/HS of 3.-3.2 are generally not the most shear stable in general. Something like ESP 30 grade would maintain grade better. But in this engine, it's completely fine and good choice.
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For this application, OP is running a 5w30 where the manufacturer recommends 0w16. I would continue with this grade even if not oil type.
For the average Jane using what Jiffy Lube dumps in ‘cuz the cap calls for it, you’re telling us you don’t think an oil that loses viscosity on its own, toss in a little fuel dilution, and top it off with the fact that Jane not only ran the engine a quart low on oil AND ‘oops’, forgot her 6k interval but got it at 10k… isn’t going to matter to the engine?
But then people here will still turn around and blame this solely on Subaru
I'm just trying to settle on a single oil for the Tundra, RX 350, Soul, and Forester and 5W30 VRP seems to fit the bill, especially for the Kia and Subaru - I'm hoping more frequent OCIs and the cleaning properties will keep the rings clean. I still have some other oils in my stash that I'm working through but 5W30 seems to be a good compromise for engines that call for either a 16 or 20 grade and experience fuel dilution.For this application, OP is running a 5w30 where the manufacturer recommends 0w16. I would continue with this grade even if not oil type.
For the average Jane using what Jiffy Lube dumps in ‘cuz the cap calls for it, you’re telling us you don’t think an oil that loses viscosity on its own, toss in a little fuel dilution, and top it off with the fact that Jane not only ran the engine a quart low on oil AND ‘oops’, forgot her 6k interval but got it at 10k… isn’t going to matter to the engine?
But then people here will still turn around and blame this solely on Subaru
No… I’m perfectly fine with 5w30 in everything. I’d probably even recommend it.
