Oil question 0w-50

[SlidingSideways]

Hey so I got a gallon of eneos 0w-50 from skymeet and I just put it in my car..
And it is -alllllmost enough- it the engine's been running, and I just turn it off, it's at the bottom of the dipstick, if I let it sit and let all the oil run down into the pan, then it's just above the 'low' mark on the stick.

Anyways, it's almost enou, but not quite...
So here comes the stupid question..

I have half a quart of royal purple 10w40 left from the last oil change... Can I put it in to top it up or is this a stupid idea?

I'm trying to avoid the 2 hr drive each way to pur automotive just to go buy a quart(only need half) of 0w50 to top it up. And I don't know anywhere else that sells it.

Watchu think?

[Super_Dude]

mix it. Don't drive around with low oil

[NismoS-tune]

I have 4 or 5 bottles of that 0-50enos I don't need (12L capacity drinks too much of it)

I can ship it...

[r33_gtst]

Is this oil a better choice for our engines?
I also am in the same boat. Won the same oil at skymeet
Not ure about using it, I used a 15w50 before an am currently using a 40

[NismoS-tune]

I have some buddies that have anything from gt500s, z06, 911s, zl1 and all run more or less regular oil. Synthetic, diesel oil, they all have they pros and cons. I run royal purple 5-30 or 10-40 and my oil never sees over 90deg and I beat that thing. Depends if you have a cooler, how often you change your oil, oil capacity, driving style... You car won't explode without that super 0-50 oil not will it necessarily run better. Choose a good synthetic and stick with it. Opinions makes the decisions. Just like saying an Evo x is better than a skyline. Opinion.

[MarusGTR]

Couple things:

Touching Low is ok if you're not tracking or if you don't have a high G straight WOT. The point of going to High or overfill is to stop starvation at high loads. There's is also the issue of less mass; your oil has less mass, gets more exposure, gets worn quicker. Same for heatsoak, more oil, less temperature change (technically, less thermal gradient).

As for mixing, this is my rules in order of importance, but I'm no expert, just universally anal:
1.Mix same brand and cold weight
2.Mix same brand
3.Mix same cold weight, with load weight as close as possible

Why cold weight? Because I assume that the cold weight has more shear thinners (additives) that could get wonky with other cold weights. I do know for a fact that low cold weights usually degrade faster. Bulk weight it's more about polymer density than additives.

What I do know is to not mix different brands, they all have different detergents/additives that could react when mixed. If IIRC the eneos is detergent-free, mix it with off-the counter detergent saturated brands and it could be bad. Anyway check bobistheoilguy for more info and this is just my opinion.

Edit: As for weight nothing beats 30 for the street with a mild application, very smooth idle. I went to 40 and hit a constant 110 during my last time attack, not too shabby (and still within the recommended OEM spec, you should increase 10 weight points over 30 weight after 100C)

[Skym]

Like coolants, never mix them. Drain and refill with same brand, weight oil.

Also shouldn't be seeing above 90 degrees C at end of main straight on racetrack and w40 is rated to over 100 degrees C (factory is 7.5w30). I noticed it's common for people to use wrong size oilcooler cores for application hence high oil temps.

Also I wouldn't run below 10w with hydraulic lifters.