Oil Recomendations

[carguy49]

I have a 2013 2.5 Outback with 71000 miles. I realize that 0W/20 is the recommended oil but was wondering over the years has the oil weight changed to combat any engine issues ?

 

[bmart]

Are you using more oil than you used to? Owners' manual usually knows best.

 

[Lou O.]

Zero weight oil (viscosity of water) is being used to save fuel, not wear and tear on your engine.
It might be wise to switch to a full synthetic 5W30 for best engine protection!

 

[bmart]

Oil is more viscous than water, even 0W.

 

[Lou O.]

According to the PhD's at GM, zero weight is the same viscosity as water, as measured in centistokes.
Do you have a PhD in Tribology? If not, I will not debate the issue further.....

 

[bmart]

Thank the gods for you and your ilk. There's no forum you won't add acid to.

 

[carguy49]

Thanks for the responses. I ended up using 0w20 with a Subaru filter. My timing chain rensioners are a bit noisey on startup and thought a heavier oil would quiet them down.

 

[Daniel Renaud]

Zero weight oil (viscosity of water) is being used to save fuel, not wear and tear on your engine.
It might be wise to switch to a full synthetic 5W30 for best engine protection!

Does Subaru say it's ok using 5W20 My Outback Manual say 0W20 My Honda use 5W20 I change oil every six month or 3000 miles

 

[UnknownInside]

According to the PhD's at GM, zero weight is the same viscosity as water, as measured in centistokes.
Do you have a PhD in Tribology? If not, I will not debate the issue further.....

lol I’m quite sure you don’t have a PhD in anything!

 

[Mark Monte]

I agree with Lou's statement: Zero weight oil (viscosity of water) is being used to save fuel, not wear and tear on your engine. High mileage engines may benefit from using 5W-30.
In those days of yore, there was nothing wrong with adding STP Oil Treatment or Hyperlube as a viscosity improvement. The idea is to compensate for wear by using a thicker oil where it matters most, like rod bearings, piston rings, and valve guides. The Zero-W is the rating for WINTER when an oil is very viscous (thick) when it is cold.
I am an old school guy and I am amazed at the new oil standards. Zero weight was unthinkable back in the Sixties.
Also, in the Sixties there was no such thing as "variabve valve tech" . The slippery Winter rating is to help
the computer control cam phasing via an electric solenoid to control oil pressure. This extrmely thin oil is not really necessary once the engine warms up. Frequent oil changes help reduce the amount of crud that develop in the oil sump. There can be a lot of soot and byproducts of combustion such as moisture and gasoline that can build up in the sump over time, so do not postpone oil changes. .