What oil will you use?
 

What oil do you plan on using?

I dont trust 20W oil in general, it has been responsible for many premature engine failures in modern cars trying to get the best eco figures possible. Unless it voids the warranty, I will use 5W30 (dino in break in period, synth after break in)

Thought it came with synth from the factory?

I would be hard pressed to accept that any 0W-20 was anything other than synthetic, depending on what you think synthetic actually means. In order to meet volatility requirements a 0W-20 is unlikely to use much conventional Group I base oil.

It is specified as required because 0W-20 is what they would have used for EPA emissions and fuel economy testing.

While you can't void a warranty, the dealership will certainly attempt to -- and likely succeed in -- void any warranty claims regarding the powertrain when they find out you were using oil not specified in the manual; even if that oil likely provides better protection.

That is where is can become dicey. The manufacturer has a vested interest, relating to CAFE requirements, in ensuring that the oil used for EPA certification is used in practice.

OW-20 should be able to work acceptably if an engine is appropriately designed.

You do have an out however:

"....Oil viscosity (0W-20 is explained here as an example):
• The 0W in 0W-20 indicates the characteristic of the oil which allows
cold startability. Oils with a lower value before the W allow for easier
starting of the engine in cold weather.
• The 20 in 0W-20 indicates the viscosity characteristic of the oil when
the oil is at high temperature. An oil with a higher viscosity (one with a
higher value) may be better suited if the vehicle is operated at high
speeds, or under extreme load conditions....."

which shows in both the BRZ & FRS owners manuals!

Now this is good news. Mine will be seeing "extreme load conditions" so I guess that can provide a justification for my choices xD

I may switch to 5W-30 for DD/AutoX use, then switch back to 0W-20 for long trips.

Recall, short trips (less than something like 3-5 miles) also fall under extreme load conditions and hard wear because the oil never actually gets to temp.

I plan to use Amsoil. Probably 0W-20 Signature at first, but switch to 0W-30 for HPDE events.

Well sort of, but not load in the sense that you might be thinking. Short trip driving stresses oil because yes it does not get up to temperature enough to evaporate any condensation from the crankcase. But oils are specifically designed to deal with the condensation issue. This performance area has nothing to do with viscosity grade.

Fuel dilution can also be an issue for cold start short trips, but much less so with accurate fuel injection. However if you are over reving when the engine is cold there is still some potential for over fueling which can get into the crankcase and dilute the engine oil. Still wise to take it easy when and engine is warming up.

They want 0W for best low temperature starting and oil delivery when cold. The lower the second part eg. 20, 30, 40..., which relates to high temperature viscosity performance the better the fuel economy.

Sooooo....which oil are you guys gonna use? Mobil 1, AMSoil, Walmart value, or vinegar oil?

Im leaning towards Mobil 1 or AMS oil. Have never used AMS oil but I am curious about it. I know for sure I will be using that stuff moto uses in his. Forgot what its called :p

As described, the number before the W indicates the cold viscosity and the number after the W indicates the hot viscosity properties of the oil. Given that this car calls for an oil that has low viscosity at low temperatures, 0W, I would stick with something that also is a 0W. But the Higher number is a little ambiguous. The lower the number is, the more the oils viscosity drops as it gets how. Changing to an oil with a higher number after the W will give you a more temperature stable oil more then anything else. The viscosity at normal operating temperature wont be effected much, but will remain in the correct operating range for the engine for a higher temperature.

I'll be running Mobile 1 0W40.

Penzoil Platinum. Good HTHS for the price and the BobIsTheOilGuy.com forums like it.

Mobil 1 and Subarus don't go together well. US Castrol is on the thinner side when it comes to HTHS. And considering my planned useage and OCI, Amsoil and RedLine are a bit pricey.

Sort of. The number after the W does not represent a rate of change of viscosity with temperature.

It does however represent a range of viscosity values at temperatures and conditions that oil producers and engine manufacturers have jointly agreed are relevent to engine operation as it relates to oil thickness. To be listed as say a "30" in an ?W-30 requires that the oil fall within a range of viscosity values for kinematic viscosity of 9.3-12.5 cSt at 100 deg C and have an HTHS(high temperature high shear) dynamic viscosity of greater than or equal to 2.9 mPas at 150 deg C. ?W-20 would be 5.6 to 9.3 cSt and HTHS greater than 2.6mPas.

HTHS dynamic viscosity requirements actually relate to temperatures and oil shear rates in connecting rod bearings as a mechanical point of reference.

http://www.tribology-abc.com/abc/viscosity.htm#dynamic

Scroll down to the table for SAE Viscosity Grades for Engine Oils1 — SAE J300 Dec 99

The industry standards in the above table show the minimum requirements that oil producers and engine manufacturers use for categorizing the flow characteristics of engine lubricants. Engine designers can then design engines knowing what properties to expect from products based on their viscosity grade.

Lower HTHS values have demonstrated better fuel economy, but because the oil is thinner at high temperature, care has to be taken to ensure engines recommending these viscosity grades are appropriately designed to use them. If an engine has been properly designed to use lower viscosity engine oils adequate film thickness should be available from the recommended viscosity grade under conditions specified by the engine manufacturer.

Now if you plan to subject the engine to higher loads and temperatures, than what the manufacturers suggests are normal, as the owners manual in this case suggests, one might want to consider an oil with a higher number after the W. Conceptually, there was however, an old rule of thumb which suggested that you have more potential for wear from an oil that is too thick at low temperture than you would get from one that is too thin at high temperature.

This can get to be a complicated subject rather quickly!

I'll go going with M1 0w-30 AFE. I really don't see the use of going with a heavier oil, unless you plan to track every weekend.

For those planning on Mobil 1, keep track of your oil consumption. If you see your engine using a lot of oil, switch to different brand.

Hey, thanks for the much more complete explanation. First off a disclaimer, I've lost a lot of the finer details in the almost decade since I studied this.

Basically what I was trying to get at was that with the periodic heavy loads that most of us will be subjecting our engines to, an oil with a better VI would be more appropriate. Also, by maintaining an oil with similar cold properties you'll ensure the oil stays within the designed operating range of viscosity, even at normal operating temperature. But, the oil won't be as proned to go out side the designed range of viscosity when we start beating on the car.

Ill probably stick to motul 5w40 for the track and summer time
and 0w20 for winter time, as I understand 0w20 is fully synthetic oil.
for 0w20 ill use the dealer supplied.

Glad the info was of help. I can get carried away in the detail having been a formulator for over 30 years.

As you have said, higher VI, simply put, is good. However VI is also a complicated subject when you layer in the effects of temporary and permanent viscosity loss as well as any fuel dilution during use of the oil.

Just for clarity sake when trying to understand low temperature performance what the numbers in the table are telling us is that a

0W?? oil is supposed to guarantee that the oil is thin enough to allow an engine to crank fast enough to start at -35 deg C and thin enough to properly pump at -40 degC.
5W-?? oil is supposed to guarantee that the oil is thin enough to allow an engine to crank fast enough at -30 deg C and thin enough to properly pump at -35 degC.
You want the oil to be thin enough to pump at 5 deg C lower than the oil being thin enough to allow the engine to crank fast enough to start to ensure that the oil gets to all the places its supposed to be!

Some may say it never gets that cold where I live! However the lower low temperature viscosity results in reduced oil drag in the engine, improves oil flow and reduces fuel consumption. Also increases power.

Damn! The only thing I've done for over 30 years is breath. :respekt: I've been in the Navy for 13 years, so far I've been an oiler, fridge tech, heavy equipment tech, Boiler operator, instrumentation tech and now I'm an electronics tech.

Sorry for the off topic everyone.

Well I had lots of different jobs but they all were related to engines oil in one form or another.

Anybody knows where Subaru sources their 0w-20 synthetic? Is it any good?

I'm pretty sure that's the absolute minimum temperature your car is guaranteed to start. From what I understand, even summer temperatures are too low for the oil to flow well, and the majority of wear occurs on startup and when the engine is still cold, and that doesn't mean cold to the human body :bonk:

Guaranteed based on the definitions. Unfortunately the SAE viscosity grading system does not have a "grade" to specify performance at lower temperatures than those associated with 0W. However that does not prevent formulation of viscosity values lower than the maximum for the grade's temperature definitions.

Butane is added to gasoline in winter, to assist low temperature starting. Butane has a flash point of -60C. So as long as the front end of the fuel can vapourize(has a low IBP), it has an appropriate distillation curve, the engine oil is thin enough to allow pumping and fast enough cranking to meet minimum start rpm, and the battery retains enough amps an engine can be started at temperatures lower than -35. Actually its usually battery cranking amps loss with temperature decrease that has the greater impact on starting ability.

".....even summer temperatures are too low for the oil to flow well, and the majority of wear occurs on startup and when the engine is still cold..."

Correct to a point but more appropriately stated as: there are benefits from using low viscosity multigrade oils even in summer.

So for Memphis weather I would it would be best to use 0w-20? What do you guys think of AMS oil?

For hot texas summers ? 5w40?

Soo, a local parts store has some signature 0w-20 Amsoil. Anyone has oil specs that Subaru wants or can explain to me what "ilsac multigrade" means?

Scion service manual is a lot clearer: API grade SL "energy-conserving", SM "energy-conserving", SN "resource conserving". Hence, Amsoil signature should work for FR-S but would it would be nice to have some confirmation from Subaru's own source.

Anyone with HTML service manual access?

I want to know whether I should go with AMS oil or Mobil 1. I used to use Royal Purple but I heard stuff about them pitting cams and stuff.

Also, any recommendations for grade I should be using in Memphis weather?

This site provides a summary applicable to trying to understand engine oil lingo

http://en.wikipedia.org/wiki/Motor_oil

to better understand the recommendations you see in an owners manual or service recommendation manual, as well as other useful information.

The owners manual remains the source for recommendations on what oil to use in terms of performance level(eg. API Service category,ILSAC Designation, etc...), viscosity grade(SAE) and drain interval recommendation relative to warranty requirements. Engine manufacturers do spend time ensuring the appropriateness of their recommendations, based on many factors including the fact that they underwrite the warranties they provide.

Consulting the engine lubricant manufacturer of your choice for their expertise regarding matching their products to specific vehicle need and application parameters is also an important part of the process of engine lubricant selection.

^In words please. I've read the manual. Does 'ilsac multigrade' mean that any GF4/GF5 0w-20 will work or is it something else?

A quote from the previously mentioned wiki
"....A new set of specifications, GF-5,[13] took effect in October 2010. The industry has one year to convert their oils to GF-5 and in September 2011, ILSAC will no longer offer licensing for GF-4...."

This discussion has been limited to pointing folks to information that can help with understanding. Specific interpretation and recommendations are the mandate of the engine manufacturer and engine lubricant manufacturer which are the best places to consult for specific details on how they interpret the use of the specifications that they recommend.

Okay, I'll repeat my question "can anyone with access to service manual tell me what it says about oil grades (like the scion one does)?". I'm sure the answer to that is not in wikipedia.

I just changed my oil with ~6qts of Castrol Syntec 0w30 since I couldnt find any full synth 0w20 in my local parts store. (they carry 0w20 or 5w20 synth blend motorcraft).
Gonna start ordering my oil and filters online, had to go to a Subaru dealership to pick up the oil filter, they said I was the first one to buy one!

I asked my sales person if she could help me with finding out what the service manual says. She couldn't find any info in the Subaru technical system for some reason, but she did tell me the specs of OEM oil - it's "0w-20 API Service SM - Energy Conserving "

Didn't you get the 2/25K service with the car? If they are using full synthetic why not let them just do it for now and keep the car covered? how many miles did you put on yours so far?

I dont know what kind of stupid service contract I have with SCION, because my dealership is halfassed. I was not about to wait around for them anyways. It had 1560mi when I dropped it off at the dyno today.

It was already clear that you don't have access to the BRZ service manual.

All Scions come with 2yr/25K service. You should not be paing a dime for oil changes. I bought mine at Avondale Toyota/Scion. Being you are in Phoenix...that narrows it to only 2 other dealers. If someone is giving you the run around let me know.