Both of these motor oils are 5 grade when cold, however, 5w30 oil is 30 grade, and 5w40 oil.
5w40 oil is not thicker as it has a higher viscosity.
5w40 with higher temperatures in summer has a higher viscosity.
Both oils are 5 grade when cold, but 5w30 is 30 grade and 5w40 40 grade when at operating temperatures.
2. 5mPas. 5w40 ensures higher pressure, but less flow.
however, I use 5w-40 Amsoil because oil in turbo cars goes through alot of abuse and deteriorates.
Jul 5, 2019 · In terms of motor oil, correct me if im wrong but I believe it's 5w-30.
. I recognize that the car calls for 5W-30 but it seems like WRX/STI owners tend to prefer a higher-viscosity oil, even if they do not.
3 to 12.
Amazon Basics Full Synthetic Motor Oil 5W-40 With Euro Formula: Best Oil For Subaru WRX 2002-2010.
In most inhabited regions a synth 5W-40 will be OK, since it will behave at least adequately from -10 to +45 or so.
On the other hand, 5w40 will not be as great as 5w30 regarding fuel consumption.
Using the OEM oil and filter will make sure you're meeting Subaru's specifications, should any warranty work ever be required.