Originally Posted By: Virtus_Probi
I have a '14 Forester XT (WRXs are NOT the only Subie turbos!!!!) and am still trying to settle on an oil. Went with dealer changes until they really screwed one up and damaged the drain plug, leading to a big mess in my garage and wasted time...I assume they were using Subie synthetic 5W30. Used M1 5W30 at first and noticed right away that cold (like parked outside overnight on ski weekends cold, -10F or lower) starts were much smoother. Then I switched to Quaker State Ultimate Durability 5W30 because it had a bit better NOACK % than M1 with similar cold viscosity, no experience with it yet in the cold but I have been getting better gas mileage this summer than the last one with the dealership oil.
I have been poking around at some of the numbers for "boutique" oils and found that Redline and Royal Purple 5W30 are too thick at cold for my liking. Amsoil Signature 5W30 looks great by the numbers all around, but is expensive and I'd have to order it online and pay shipping. Seems like it should be a small thing, but I also don't like it coming in 4 quart instead of 5 quart jugs because I can't stand single quart bottles laying around (need almost 6 quarts for my change). If I tried it once and was happy with it, I'd be fine with ordering 4 gallon jugs at a time and getting free shipping, but I'm not going to do that for a first try.
Some have suggested using 0WXX oils due to my concerns about cold starts, but I have noticed that they tend to have higher NOACK %s than 5WXX oils from the same brand...I'd like to compare the numbers for M1 0W40 and 5W30 head to head, but they don't give NOACK % for either or the pour point for the 0W40 (they have the same flash point). I do see that Amsoil Signature 5W30 and 0W40 have the same pour point while the 0W40 has a lower flash point and a higher NOACK %...it is also quite a bit thicker than the 5W30 at "normal" temps, which I suppose is what most people are after.
https://www.amsoil.com/lit/databulletins/g2880.pdf
NOACK:
M1 0W40: 8.7%
Castrol 0W40: 9.1%
All MB 229.5 oils have to have NOACK of 10% or less.
I have a '14 Forester XT (WRXs are NOT the only Subie turbos!!!!) and am still trying to settle on an oil. Went with dealer changes until they really screwed one up and damaged the drain plug, leading to a big mess in my garage and wasted time...I assume they were using Subie synthetic 5W30. Used M1 5W30 at first and noticed right away that cold (like parked outside overnight on ski weekends cold, -10F or lower) starts were much smoother. Then I switched to Quaker State Ultimate Durability 5W30 because it had a bit better NOACK % than M1 with similar cold viscosity, no experience with it yet in the cold but I have been getting better gas mileage this summer than the last one with the dealership oil.
I have been poking around at some of the numbers for "boutique" oils and found that Redline and Royal Purple 5W30 are too thick at cold for my liking. Amsoil Signature 5W30 looks great by the numbers all around, but is expensive and I'd have to order it online and pay shipping. Seems like it should be a small thing, but I also don't like it coming in 4 quart instead of 5 quart jugs because I can't stand single quart bottles laying around (need almost 6 quarts for my change). If I tried it once and was happy with it, I'd be fine with ordering 4 gallon jugs at a time and getting free shipping, but I'm not going to do that for a first try.
Some have suggested using 0WXX oils due to my concerns about cold starts, but I have noticed that they tend to have higher NOACK %s than 5WXX oils from the same brand...I'd like to compare the numbers for M1 0W40 and 5W30 head to head, but they don't give NOACK % for either or the pour point for the 0W40 (they have the same flash point). I do see that Amsoil Signature 5W30 and 0W40 have the same pour point while the 0W40 has a lower flash point and a higher NOACK %...it is also quite a bit thicker than the 5W30 at "normal" temps, which I suppose is what most people are after.
https://www.amsoil.com/lit/databulletins/g2880.pdf
NOACK:
M1 0W40: 8.7%
Castrol 0W40: 9.1%
All MB 229.5 oils have to have NOACK of 10% or less.