ok guys i need your opinion. as you can see in my sig i have an 12'outback last year of the ej's before they went to the fb's. anyway, it calls for 5w30 on cap and "somewhat" in the OM. however, it also lists 5/10w40 when temps allow. does anybody know the tolerances of this engine if i actually tried a 20wt or am i asking for trouble with the thinner oil. would this engine tolerate a 40wt better than a 20wt?
subaru EJ25
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I would not try a 20 weight oil in this engine unless it is on the recomended list by Subaru. The increase in mileage if any, will be lost in the day to day variability. I'd just use a good grade of 5w30. Ed
Originally Posted By: subaroo
ok guys i need your opinion. as you can see in my sig i have an 12'outback last year of the ej's before they went to the fb's. anyway, it calls for 5w30 on cap and "somewhat" in the OM. however, it also lists 5/10w40 when temps allow. does anybody know the tolerances of this engine if i actually tried a 20wt or am i asking for trouble with the thinner oil. would this engine tolerate a 40wt better than a 20wt?
I currently use 10w-40 in mine with no problem but i noticed the best mpgs with 10w-30. I plan on switching back next oil change. I would not use a 20 weight just due to the fact that the ej25 has pretty big tolerances that need a thicker oil to fill them. Anyone on here will tell you 5w-20 is too thin for an EJ. Btw, i already asked this question and everyone said no.
ok guys i need your opinion. as you can see in my sig i have an 12'outback last year of the ej's before they went to the fb's. anyway, it calls for 5w30 on cap and "somewhat" in the OM. however, it also lists 5/10w40 when temps allow. does anybody know the tolerances of this engine if i actually tried a 20wt or am i asking for trouble with the thinner oil. would this engine tolerate a 40wt better than a 20wt?
I currently use 10w-40 in mine with no problem but i noticed the best mpgs with 10w-30. I plan on switching back next oil change. I would not use a 20 weight just due to the fact that the ej25 has pretty big tolerances that need a thicker oil to fill them. Anyone on here will tell you 5w-20 is too thin for an EJ. Btw, i already asked this question and everyone said no.
Originally Posted By: subaroo
ok guys i need your opinion. as you can see in my sig i have an 12'outback last year of the ej's before they went to the fb's. anyway, it calls for 5w30 on cap and "somewhat" in the OM. however, it also lists 5/10w40 when temps allow. does anybody know the tolerances of this engine if i actually tried a 20wt or am i asking for trouble with the thinner oil. would this engine tolerate a 40wt better than a 20wt?
Thicker cant hurt anything except mpg,
thinner could theoretically cause mechanical failure.
Those engines are an older design and werent designed for 20wt.
Will you damage it probably not.. but why take chances.
Also you talking about going thicker or thinner..
why not just stay with the recommended grade of 5w30?
ok guys i need your opinion. as you can see in my sig i have an 12'outback last year of the ej's before they went to the fb's. anyway, it calls for 5w30 on cap and "somewhat" in the OM. however, it also lists 5/10w40 when temps allow. does anybody know the tolerances of this engine if i actually tried a 20wt or am i asking for trouble with the thinner oil. would this engine tolerate a 40wt better than a 20wt?
Thicker cant hurt anything except mpg,
thinner could theoretically cause mechanical failure.
Those engines are an older design and werent designed for 20wt.
Will you damage it probably not.. but why take chances.
Also you talking about going thicker or thinner..
why not just stay with the recommended grade of 5w30?
JTK
$100 Site Donor 2025
5w30 is the recommended oil for the EJ253, but run anything you like per the viscosity chart in your 2012's manual. 2012 was the last year Subaru USA included this chart. My 2012 Legacy's manual showed it too.
You can bet the new FB series 0w20 recommendation stems from marketing and the bean counters as opposed to being mostly an engineering recommendation.
You can bet the new FB series 0w20 recommendation stems from marketing and the bean counters as opposed to being mostly an engineering recommendation.
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Don't overthink oil choice in an n/a EJ engine. My daughter's 2.5RS gets Pennzoil High Mileage conventional 5W-30 or 10W-30 at 5-7k+ miles. Before that it got Max Life 5W-30. Here's a 2009 Outback 8k mile uoa on Mobil conventional:
https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2375274
-Dennis
https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2375274
-Dennis
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5W30 or 10W30.
01 forester EJ25 350000 miles with whatever 5w30 was on sale. Lots of 10000 mile oil changes and neglect.
i doubt any 0whatever oil will make a bit of difference.
i doubt any 0whatever oil will make a bit of difference.
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Subies tend to use a little oil when you run oils on the "lighter" side.
I would not sacrifice longevity for MPG's. These engines will run forever but were not known for their MPG's. It is what it is.
I would run a stout 30w like GC the car will thank you for it.
Jeff
I would not sacrifice longevity for MPG's. These engines will run forever but were not known for their MPG's. It is what it is.
I would run a stout 30w like GC the car will thank you for it.
Jeff
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Lots of people on NASIOC use GC. I used GC year round when I had my Saabaru 9-2X.
I experimented with 20 oils in the EJ25 and discovered nasty little rattle at hard 1 -> 2 shift. If you have the CVT you might be OK since there will be no shock load on the engine.
Try Pennzoil Conventional YB 10w30...Made my EJ25 smooth and quiet and increased fuel mileage over anything else I tried.
Try Pennzoil Conventional YB 10w30...Made my EJ25 smooth and quiet and increased fuel mileage over anything else I tried.
I have tossed in 20 weight oils in my '99 without harm. It was leftovers from the fit. I actually have a lot of 5w20 in my stash and the Subaru will likely get some (and I will cut it with 5w30 or 10w40). Because it is under warranty (2012), stick to the recommended/allowed weights in the owners manual. Once you are paying for the repairs, use whatever you like. Using a 20 weight is not the end of the world. A 40 weight works well in the Subie and I sometimes run it in the summer if I can find a sale. MPG does go down a lot if you are doing short trips on 10w40.
I've used Idemitsu, RT6, Mobil1, QSGB, Mobil 5000. Pick any 5W-30 and use with confidence.
Originally Posted By: subaroo
ok guys i need your opinion. as you can see in my sig i have an 12'outback last year of the ej's before they went to the fb's. anyway, it calls for 5w30 on cap and "somewhat" in the OM. however, it also lists 5/10w40 when temps allow. does anybody know the tolerances of this engine if i actually tried a 20wt or am i asking for trouble with the thinner oil. would this engine tolerate a 40wt better than a 20wt?
..I have a 1987 VW Diesel Turbo, with 300,000+ mi... 1990 subi loyale with 262,000mi .. 1986 subi turbo with 219,000mi ...2001 Outback with 180,000 and with this car no oil added between changes,...all running on 5w/20 for many yrs now..subaru tolerances are extremely tight and every once in a while will have the oil analysed always having good results mostly using MC 5/20 changed every 5000mi..even for my '86 subi the oil pressure is more then needed for the corresponding rpm and have driven either subi many times in the hot texas weather with no problems..the latest oil anal. is an experiment with an oil mixture here at .. https://bobistheoilguy.com/forums/ubbthreads.php/topics/3220890/1
ok guys i need your opinion. as you can see in my sig i have an 12'outback last year of the ej's before they went to the fb's. anyway, it calls for 5w30 on cap and "somewhat" in the OM. however, it also lists 5/10w40 when temps allow. does anybody know the tolerances of this engine if i actually tried a 20wt or am i asking for trouble with the thinner oil. would this engine tolerate a 40wt better than a 20wt?
..I have a 1987 VW Diesel Turbo, with 300,000+ mi... 1990 subi loyale with 262,000mi .. 1986 subi turbo with 219,000mi ...2001 Outback with 180,000 and with this car no oil added between changes,...all running on 5w/20 for many yrs now..subaru tolerances are extremely tight and every once in a while will have the oil analysed always having good results mostly using MC 5/20 changed every 5000mi..even for my '86 subi the oil pressure is more then needed for the corresponding rpm and have driven either subi many times in the hot texas weather with no problems..the latest oil anal. is an experiment with an oil mixture here at .. https://bobistheoilguy.com/forums/ubbthreads.php/topics/3220890/1
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