Fuel Dilution: 2022 Subaru Crosstrek FB20D 2,774mi OCI Schaeffer Supreme 9000 0W-20

[dezlpwr]

Despite Subaru's 6,000mi OCI recommendation, I will continue to do 3,000mi OCIs as long as fuel dilution continues. I'd hate to see the fuel dilution at 6,000mi if it is already flagged under 3,000mi. I just switched to Pennzoil Ultra Platinum 0W-20. It is easier for me to obtain than the Schaeffer. That obviously won't affect the fuel dilution. Vehicle is rarely idled, and sees very few short trips. 50/50 mix of highway and city driving. Titanium has been confirmed to be in the "old formula" Schaeffer oil that I have been using. They no longer use titanium in their new formula 0W-20 oil.

 

[Greasymechtech]

Toss a pint of Schaeffer's 132 into it, secretly, and see how it does for that 3k interval.

The other option is to ignore the 0w20 and use a synth 5w30 for a couple runs and see how it looks.

BTW, other than fuel/visc, nothing wrong with the UOA. Your engine broke in nicely and doesn't have a scary metal content.

 

[dezlpwr]

Toss a pint of Schaeffer's 132 into it, secretly, and see how it does for that 3k interval.

The other option is to ignore the 0w20 and use a synth 5w30 for a couple runs and see how it looks.

BTW, other than fuel/visc, nothing wrong with the UOA. Your engine broke in nicely and doesn't have a scary metal content.

I'm done with Schaeffer's. Great stuff but pricey and hard for me to get now. I have three 5 qt jugs of Pennzoil UP 0W-20 on the shelf so in 9,000mi when these three jugs are gone, I think I'll switch to Pennzoil UP 5W-30 and see how that looks after 3,000mi. I'm thinking much better! I agree wear metals are looking good.

 

[SubieRubyRoo]

I'm done with Schaeffer's. Great stuff but pricey and hard for me to get now. I have three 5 qt jugs of Pennzoil UP 0W-20 on the shelf so in 9,000mi when these three jugs are gone, I think I'll switch to Pennzoil UP 5W-30 and see how that looks after 3,000mi. I'm thinking much better! I agree wear metals are looking good.

Give that thing a 100 mile highway trip every 500 miles and fuel will come down… you short trip this thing often?

 

[dezlpwr]

Give that thing a 100 mile highway trip every 500 miles and fuel will come down… you short trip this thing often?

Lol did you not read what I posted? Rarely short tripped or idled. This oil change included a 500mi round trip highway trip to the ocean. Half of that was at 70-80mph.

 

[dezlpwr]

Give that thing a 100 mile highway trip every 500 miles and fuel will come down… you short trip this thing often?

What confuses me is that with this oil sample, there was more highway driving than the other previous ones and the fuel dilution went up! Ocean trip, several 70mi round trip highway trips to the airport and back. Can someone explain that one to me?

 

[Quattro Pete]

Is fuel dilution common on these engines? Both FB20D and FB25D as well?

 

[benjy]

Subaru is fairly new to DI so theres a learning curve as they TRY to get better MPG's while keeping the EPA happy!! using a xxW30 oil is often noted for oil getting fuel in it as a thinner 30 is surely better than an already thin 20 getting thinner unless its a thick 20!! ester oils also said to be better BUT $$$$

 

[dezlpwr]

Is fuel dilution common on these engines? Both FB20D and FB25D as well?

Yessir and many other newer DI engines running 0W-20 oil. I think a 6000mi recommended OCI is dumb running 0W-20 oil. I refuse to do it! I'm going to try a 5W-30 and 3000mi OCI in the future when I use up my stock of 0W-20, and if it does better, I may extend the OCI.

 

[SubieRubyRoo]

Lol did you not read what I posted? Rarely short tripped or idled. This oil change included a 500mi round trip highway trip to the ocean. Half of that was at 70-80mph.

Been a long day.

 

[SubieRubyRoo]

Been a long day.

Woke up at 0145 EST and drove 2 hours to IND, landed in SEA at 1130PST and just walked out of work at 1630PST. Not looking forward to a 2240PST to 0545EST redeye on Thursday, either…

 

[SubieRubyRoo]

Yessir and many other newer DI engines running 0W-20 oil. I think a 6000mi recommended OCI is dumb running 0W-20 oil. I refuse to do it! I'm going to try a 5W-30 and 3000mi OCI in the future when I use up my stock of 0W-20, and if it does better, I may extend the OCI.

Why does it feel like we’re going to end up going back to the EJ25 stalwart, Rotella T6 here?

The non-DI FB25 is not really a diluter IME. Seems like simply going to a much higher pressure, fiber nozzle PI would mitigate nearly all of the DI pitfalls while retaining a majority of the minor “pluses” of DI…

 

[haggler]

Unless you're concerned about warranty, there is no reason not to run a 5w30 if concerned about dilution. Then you can take the OCI to atleast 5k. But otherwise the UOA looks fine. I'd run it 5k and see if there is any substantial difference in fuel, I bet not.

 

[dezlpwr]

Unless you're concerned about warranty, there is no reason not to run a 5w30 if concerned about dilution. Then you can take the OCI to atleast 5k. But otherwise the UOA looks fine. I'd run it 5k and see if there is any substantial difference in fuel, I bet not.

What I don't get is this last oil sample had the most fuel dilution of any, yet had the most highway miles. Shouldn't the fuel dilution be lower? My warranty goes to 36,000mi so I may wait until then and then switch to 5W-30. Why wouldn't the fuel dilution increase exponentially as the time on the oil increases?

 

[Quattro Pete]

Is OAI a reputable lab when it comes to fuel dilution testing? I know some labs just guesstimate fuel dilution from flash point which is not accurate.

Looks like OAI uses GC, so that should be reliable, I'd think.

 

[Oillover]

Yessir and many other newer DI engines running 0W-20 oil. I think a 6000mi recommended OCI is dumb running 0W-20 oil. I refuse to do it! I'm going to try a 5W-30 and 3000mi OCI in the future when I use up my stock of 0W-20, and if it does better, I may extend the OCI.

I agree.
I've been cutting my stash of 0w20 with some 15w40 until it's gone.
Then I'm switching over to a steady diet of 5/10w30

 

[oggb]

Normal for the FB engines based on other UOAs we've seen around here

 

[dezlpwr]

Is OAI a reputable lab when it comes to fuel dilution testing? I know some labs just guesstimate fuel dilution from flash point which is not accurate.

Looks like OAI uses GC, so that should be reliable, I'd think.

Yup, owned by Amsoil I do believe. GC is WAY more accurate than the flashpoint method that Blackstone uses. I was a Blackstone customer for years but recently switched to OAI because of the fuel dilution inaccuracies at Blackstone. If it weren't for this, I'd probably still be at Blackstone. I do like the OAI app. It is very user friendly.

 

[haggler]

What I don't get is this last oil sample had the most fuel dilution of any, yet had the most highway miles. Shouldn't the fuel dilution be lower? My warranty goes to 36,000mi so I may wait until then and then switch to 5W-30. Why wouldn't the fuel dilution increase exponentially as the time on the oil increases?

It could be a sampling difference or something along those lines, the mileage is close enough. Wear looks fine. If I was you I'd sample at 5k. If you ran 5w30 you'd probably have a higher viscosity or similar after 5k.

 

[Rand]

Yep my fb25 gets 0w20 in the winter and I will probably use 5w30 in the other 2 changes.
Since I change it 3 times a year it averages around 3500miles for the winter oci and 4500 for the other oil change intervals.

Also not helping is the sump size.
2011 took 5.7qt to full line
2015 was 5.4qt

This one is full at 4.2qt last time(book says 4.4)
Reduce the sump size by 25% and add DI.. yep.. not going extended or maybe even standard intervals.
of course I have 100 qts of oil in basement from clearance so its very cheap to change the oil.