Curious - which weight of Redline oil do you recommend for this car? What's in your shop car?

Asking because this thread is all over the place.

If you contact Red Line, they will recommend 0W-20.

-Dennis

I will be using the newer Eneos 0w20 GF-5. FT-86 Speedfactory has it for a decent price.

http://ft86speedfactory.com/eneos-0w...uarts-248.html

I'll be using whatever 0w-20 oil I can get on sale. This time, that was Castrol Edge...next time, who knows.
The difference between commonly available synthetic oils will be statistically insignificant over the life of your average engine, especially considering our cars are naturally aspirated.

If you track the car, then choose an oil to match. Even then, the primary concern is viscosity. Toyota/Subaru specified roughly a 5.2-9.3cSt (20 weight) oil for this engine, so choose an oil that will fall within these specifications at the oil temperatures you are likely to see. For a street car, this would be your average 20 weight oil. If you track the car, and see higher oil temperatures, you'll probably need to step up to a 30 weight or even a 40 weight oil.
A 40 weight oil at 212 degrees F (common temperature on the "street") will be around 14cSt. This same oil at 266 degrees F (common temperature on the "track") will be around 8cSt.

If you use an oil cooler, then everything changes.

Interesting logic. It's probably also worth mentioning the viscosity at start-up. At 60F, a 5W-40 will be approximately 100 centiStokes thicker than a 0W-20.

If the temp is 50F, the 5W-40 will be approximately 180 centiStokes thicker than a 0W-20. My figures are based on using Castrol Edge 0W-20 and 5W-40 and a viscosity calculator.

I would not go with a 40 grade oil on stock internals no matter what the conditions.

-Dennis

Everyone has their logic. Here is mine. I based my selection off Mobil 1 Extended performance because it is readily available, reliable, and relatively cheap. Plus I believe that Mobil/Exxon has more money than any other company out there to develop lube.

If anyone has information about certifications and industry approvals for other brands, it would be nice to see for comparison's sake.

This PDF is gold


1. The Mobil 1 EP line only comes in 5w20, 5w30, and 10w30 flavors because these are the only viscosities that are stable/resist breakdown under a stable load. 0w does not last long enough to receive the proper industry approvals

2. I would consider these three viscosities to be within "spec."

3. protection: 10w30 > 5w30 > 5w20. Why? Look at the ACEA and industry certifications. Google them if you must. They relate to breakdown over time and under load. 10w30 is factory spec for supras.

4. gas mileage: obviously 5w20 will be better than the others due to a lower viscocity.

I would sacrifice mpg and run 5w30 in mine, 10w30 if reasonably boosted, and 5w20 at the bare minimum...

5W-20 is usually even more stable than 5W-30 since more viscosity modifiers are used to create the 5W-30 and many 5W-30's shear to a 20 grade anyway. Also, notice the difference in ZDDP levels between M1 0W-20 and 5W-20 in Mobil1's chart (although manufacturers do increase other anti-wear additives when ZDDP is reduced).

The thing about some of other specifications, like ACEA A1/B1 or even some of the manufacturers specs (like dexos), is that some oils are actually submitted to these bodies and receive formal approvals, while some oils claim to meet these specs but are not actually submitted for certification. You need to look very carefully at language such as "exceeds the requirements of" or "recommended for". Not that it really matters at the end of the day for most applications on this forum.

More ACEA info here:
http://www.acea.be/images/uploads/fi..._Sequences.pdf

To get an idea of the differences in oil specs (API, ACEA, and manufacturers specs), this is a neat tool:
http://www.lubrizol.com/EngineOilAdd...l/default.html

Keeping in mind the disclaimer listed on the site:
-Dennis

Went with Royal Purple 5W20 at ~6000 miles, first oil change was at the subie dealership at ~2900 miles.
My goodness it's not cheap. Picked it up form Autozone for $9.79 /Qt.

Ended up filling approx. 5 1/2 Qts.

Talk about bad timing.
http://www.ft86club.com/forums/showthread.php?t=28333
:D

-Dennis

Wait, every time I read one of these threads I get more confused. So the RP 0w20 isn't good? Better to use the 5w20? I've got 12 qts of RP 0w20 left at home and was going to go with Mobil 1 0w20 after I used that up, but now I'm thinking of going out and picking up some more RP 0w20 at Pepboys with that deal they've got going.

Experts please advise...

Also, I get more confused with regards to 0w20 vs 5w20. So what are the benefits, if there are any, to running 5w20 as opposed to 0w20? And in simple terms please. :thanks:

Its important to point out that virtually all 0w-20 oils are synthetic, yet some 5w-20 oils are not, and there is a reason for this.
At operating temperature, they are both 20w oils. The difference is how viscous they get at cold temperatures, and by cold, I mean below freezing.

In day to day use for most of the year, 5w-20 and 0w-20 are completely interchangeable.

However, it could be argued that most 0w-20 oils are better "built" per say. They usually have a higher viscosity index, which will reduce cold start wear and increase efficiency. The trade off is that they are potentially more prone to shearing out of grade (thinning with use). However, 0w-20 oils are historically very shear stable.


If you are buying synthetic oil, then there is no reason not to buy 0w-20. Chances are you are buying a better product. There is always the exception to the rule however...

Okay that does stink, but when you said bad timing I was thinking someone had some engine malfunction or something using RP. BTW, my first name is Dennis as well......crazy....not really, just a coincidence.

Yes, a 0W-20 is important when you take trips to the North Pole. :D

A 0W is tested at -35C and a 5W is tested at -30C.
ASTM D5293- Test Method for Apparent Viscosity of Engine Oils Between -5 and -35 C Using the Cold Crank Simulator This test method covers the laboratory determination of apparent viscosity of engine oils at temperatures between –5 and -35C and at high shear rates.


http://www.pqiamerica.com/coldcrank.htm

Using a viscosity calculator like this one , you can get a general idea of how thick an oil is at a given temperature. Note that below 0C, it isn't as accurate as it is above 0C. You just need to go to the oil web sites to get the 40C and 100C from the product data sheets.

At operating temp., it's a pretty narrow range of viscosities (actual viscosity, not the grade listed on the bottle). A 20 grade starts at 5.6 cSt's and goes to 9.29 cSt's. But if you compare a 0W-20 vs. a 5W-20 at 0C (like Mobil1), the difference is more dramatic. 324.4 cSt's vs. 412.5 cSt's. It all comes down to what will give you the best fuel economy in government tests. Just do some reading on CAFE and CAFE credits. [ame="http://en.wikipedia.org/wiki/Corporate_Average_Fuel_Economy"]Corporate Average Fuel Economy - Wikipedia, the free encyclopedia[/ame]

It's really splitting hairs between a 5W-20 and 0W-20 though. Most new Subaru turbo owner's are trying to figure out what to run because so many people on the boards run 5W-40, but Subaru of America dropped 5W-40 from the owner's manual and 5W-40's have done very well in turbo's.

-Dennis