Opinions on Subaru fb engines and oil weight?

[hansj3]

I currently have to change the wife's oil. She has a 2015 Subaru Forester with the fb25 engine, and a 6-speed. That combination is known for drinking oil, and hers is no exception. We had an oil consumption test done, but it just greased by at 75000 miles and they wouldn't put a short block in.

I get it neither would I, but I also don't like adding oil as frequently as I have to. I know outside of the US the FB motor was spec'd with thicker weights than in the US, does anybody have any experience running a 5w30 in a Subaru FB motor? Or is there a 0w20 that is really resistant to oil consumption?

 

[gathermewool]

It's the nature of the beast. I don't think you'll find anything that will resolve the oil consumption issue. The best you can do is try something new and observe the outcome.

 

[Rand]

both times I had oil consumption tests on fb25's they overfilled at the dealer... and I made them drain some out.
and both times it failed.

Its a piston ring sealing issue and annoying but the engine wont explode..

There is a 2013 outback fb25 w/6 speed in the family..
and I owned 2011 and 2015 foresters both with manual transmissions.

 

[SubieRubyRoo]

Try Castrol 0W40 from WM to see if that quells it's thirst some. The Castrol exceeds every spec the FB needs, and thickens up some to try to keep it in the crankcase. I'd buy two jugs to start, then buy one jug each time for the next 4 OCI's and just pull the 6th quart from the 2nd jug.

 

[hansj3]

Will the 40 weight trip any codes? I know some oil solenoids are sensitive to oil weight (mostly Honda, but Still)

 

[geeman789]

I have three cars ... Honda, Mazda, Subaru. Two of them use a MICROSCOPIC amount of oil, one uses WAYYY more ... guess which one?

Yep, the Subaru. Currently at almost 100 k miles, car has been the most reliable car I have ever owned. Nothing has broken or stopped working in 8 years, but it does lose oil. No visible leaks or puddles, no blue smoke, but it does use about a quart every 2 - 3 k miles, give or take. I run 0w30 in the winter, and something thicker in the summer. Current fill is PP Euro 5w40. Seems to be consuming oil at about 1 quart every 3 - 4 k miles , so a little better. Engine runs perfect, smooth and quiet, all good. I just check my oil once a week, and top up as needed.

I would try a thin 40 grade oil in the FB25. It won't hurt anything, you MIGHT drop a couple of 1/10's in mpg, the engine will probably be quieter, and you MIGHT consume less oil. M1 0w40, Castrol 0w40, PP Euro 5w40 etc. are all thin 40 grades, try one for the summer and see what happens.

 

[gathermewool]

The manual FB's have been known to consume oil for a long time. I truly do feel for you guys who bought in not having known it beforehand.

I've owned five Subarus now:

'06 WRX: purchased new
-> traded cars with friend at ~40k miles (my WRX for his Civic SI)
-> no oil consumption

'97 LGT: purchased with ~175k miles, as a beater car
-> gave it to my sister with ~225k miles
-> sporadic oil consumption, never to exceed 2 qts in ~6k miles

'08 STI: purchased new
-> hit by lady, causing $20k in damage (USAA didn't total)
-> ~60k miles, traded it for our '14 FXT after a year of repair attempts
-> no oil conumption

'14 FXT: purchased new --> ~68k miles so far
-> no oil consumption or is made up by fuel dilution

'15 Legacy: purchased last year, with ~32k miles --> ~48k miles so far
-> no oil consumption

 

[JohnnyJohnson]

Originally Posted by gathermewool
It's the nature of the beast. I don't think you'll find anything that will resolve the oil consumption issue. The best you can do is try something new and observe the outcome.


The reason I'll probably never buy a Subaru.

 

[gathermewool]

Originally Posted by JohnnyJohnson
Originally Posted by gathermewool
It's the nature of the beast. I don't think you'll find anything that will resolve the oil consumption issue. The best you can do is try something new and observe the outcome.


The reason I'll probably never buy a Subaru.


So far as I know, Subaru is only having oil consumption issues with their MT vehicles with the FB 2.5L.

 

[jbutch]

Originally Posted by JohnnyJohnson
Originally Posted by gathermewool
It's the nature of the beast. I don't think you'll find anything that will resolve the oil consumption issue. The best you can do is try something new and observe the outcome.


The reason I'll probably never buy a Subaru.


Subaru gets a bad rep for this, but many engines of many manufacturers has the same issue. Some of Honda's K24 engine has the same issue, but it is still a good engine.

 

[HowAboutThis]

Originally Posted by hansj3
I currently have to change the wife's oil. She has a 2015 Subaru Forester with the fb25 engine, and a 6-speed. That combination is known for drinking oil, and hers is no exception. We had an oil consumption test done, but it just greased by at 75000 miles and they wouldn't put a short block in.

I get it neither would I, but I also don't like adding oil as frequently as I have to. I know outside of the US the FB motor was spec'd with thicker weights than in the US, does anybody have any experience running a 5w30 in a Subaru FB motor? Or is there a 0w20 that is really resistant to oil consumption?


I used to run 5w30 or 0w30 in a '13 Crosstrek. It drank the 0w20 and drank the w30, too. Currently caring for an '05 Forester, or '06 I always mix it up. Anyway, uses oil, too. About a quart every 2-3k miles. I'm running 10w30 in it and 5w30 in winter. Makes no noticeable difference in consumption.

 

[SR5]

In Australia, for the 2015 Forester with 2.5L engine, they say you can use either 0W20 or 5W30, your choice.

A mate here has one, and he uses 5W30 and sometimes a 40 grade.

 

[Hounds]

Originally Posted by SubieRubyRoo
Try Castrol 0W40 from WM to see if that quells it's thirst some. The Castrol exceeds every spec the FB needs . . . .

Good suggestion. (Excellent, actually.) Either Castrol's 0W30 (if you can find it) or the 0W40 (not the 5W40) -- i.e., the "go to" recommendation for Volkswagen's 2.0L GTI motor -- would perform well here.

 

[ctechbob]

So, is the problem caused by wear, or coked up oil scraper rings?

If its plugged up rings, I'm going to throw out the 'try the Valvoline Premium Blue Restore' line.

 

[NO2]

The '12-'14 FB engines have a TSB for 100K miles for oil consumption. We have one. The threshold is 1Q/3500 miles, according to the dealer.

 

[Gasbuggy]

How many miles before they won't put an engine in it? I would go for a retest and make sure my car fails...

 

[Rob_Roy]

Oil viscosity didn't seem to make a difference in how much oil our 2014 Outback 2.5 consumed. What DID make a difference was how the car was driven. It would go months hauling the kids around and not need any oil, but if we went on a trip at 75MPH with that little engine streaming up the hills, it would need oil after a fee tanks of gas.

 

[T-Stick]

I broke two Crosstreks in and had negligible oil consumption in 7,500 miles. I am of the opinion that for the 1st 1,000 when you are not to exceed 4k rpms that you should slowly take it up to 4K rpms and then allow it to decelerate. You can do this with the paddle shifters. After 1,000 I successively ran it harder with acceleration to the redline and deceleration. I would do this once a day to help run the rings in. Deceleration at high rpms going down a steep hill helps to give the reverse pressure. In the end both cars were that tight that they did not need to add oil between changes even with a 20w oil.

My '16 Crosstrek has 73k on it and has never had any repairs other than normal and preventative maintenance. I've never owned such a reliable vehicle before.

I have an 09 Tribeca with the 3.6 and it used about a 1/2 quart every 2k when I bought it used. I have been using a 5w30 high mileage oil and it has certainly lessened the usage. Long trips with hills definitely increases usage over the around home short tripping.

 

[scotthershall]

I had a 2014 Crosstrek before my 2014 Camry. I bought the Crosstrek with about 40K-ish miles on it, and had it until about 85K. I found it sometimes used about a quart of oil over the 7500 mile interval... sometimes not. I found the engine "liked" Valvoline/Napa 0w-20 and hardly used a drop of that. The engine consumed oil at a much higher rate when I used Pennzoil Platnium and Carquest house brand (made by Amelie) 0w-20... so much so that I learned the car had a low oil level light unlike many other cars.

It was very odd indeed. It's the only car I've had that appeared to be choosy about it's oil.

 

[digger327]

So far my 2017 FB20 engine in a Crosstrek has not used any 0w20 oil between changes. So far it's had dealer bulk Mobil 1 and Quaker State QSUD in it. Next up is PP or Zepro D1G2. Only Subaru engine i ever had that used oil was a 99 Ej25 engine, it sucked Castrol Edge like a cold beer on a hot day. Strangely on all other oils, Mobil 1, Valvoline, Pennzoil Platinum there was no usage.