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Using 0W40 instead of 0W20 oil on the 2013 2.5 OB

47915 Views 25 Replies 17 Participants Last post by  avenger09123
Hi friends,

Possibly a dumb question (as I for some reason cannot fully wrap my head around the oil viscosity thingy), but my 2013 2.5 Prem CVT manual recommends 0W20 synthetic oil. If I was to use Mobil 1's 0W40 oil instead, would it do any harm, either in short run and/or over time?

I currently have only a few hundred miles on my 2013 OB, but plan on doing first new car oil/filter change around 1000 mile mark.

plex :cool:
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To oversimplify, the first number is cold viscosity (start up or severe cold). The second number is hot viscosity (operating temp). If the recommendation is 0w20, then you can substitute anything with the last number of 20. You could also do a 30 if you felt like it. But a 40 is diesel and high temp territory. No need for that. It wouldn't hurt anything other than your mpg, but there's no reason to do it unless you were driving through the desert uphill.

Reasonable substitutes for 0w20 would be a 5w20, 0w30, or 5w30. Anything over that would be pointless. The only reason they recommend 0w20 over the previous 5w30 is efficiency. It is simply to help with gas mileage.
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Ehh. No need to blindly follow. Its not mother subaru, its soa trying to meet MPG standards. But 0w40 is pointless. You could safely use a 5w30 with no issues.
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