Oil too thin?

[austai]

Hi,

About a month or so ago, I put 3 quarts or Mobil 1 0w30 plus 1 quart synthetic 15w40 (not Mobil 1) in my '01 Miata. I figured the 0w30 would be OK in winter and the 15w40 would add some thickness to the oil.

Well, since the oil change, it seems there is more valvetrain noise compared to when I had Mobil 1 10w30 before. The noise is nothing obnoxious but I can't help but notice it.

Could my oil mix be too thin? Am I causing needless wear and tear?

With less than 1K miles since the oil change, I'm thinking of draining it and putting in a good, thicker conventional oil.

Thanks

 

[1999nick]

What kind of a synthetic 15W40 did you use? I never have seen a synthetic 15W40.

 

[Doc8404]

just run the visc the manual says!

 

[austai]

Quote:

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What kind of a synthetic 15W40 did you use? I never have seen a synthetic 15W40.

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It might have been 15w-50. It was probably at least 5 years old but I didn't want to waste it.

 

[B00SS]

Quote:

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It might have been 15w-50. It was probably at least 5 years old but I didn't want to waste it.

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Overall you're only slightly thicker. I wouldn't think it would be a problem, but if you're hearing the noise, that is hard to overlook.

 

[Syntec-Man]

0w 30 is not thin

 

[mitchcoyote]

Don't try and blend your own oil. Go by the owners manual recommendation...

 

[Kitto]

I am thinking you blend a wrong oil??
I have a 96 Miata, I just put Mobil 1 0w40 and I swear the car run a lot better than 5w30 conventional and no more HLA tick.
I am in chicago and it's around 0F" these few days.

 

[austai]

Maybe the blending is the problem. I'll get some good conventional oil, instead.

BTW, which conventional oil handles regular 6000-7000 RPM revs the best? I guess that quality would be shear resistance?

 

[jorton]

Valvoline racing oil.