Does conventional provide more 'cushion'?

[frmtbiker]

Originally Posted By: d00df00d
They might be the same grade, but remember that each grade represents a small range of viscosities.


Right, OK, same grades (5w30)... I was under the impression grade and viscosity were the same.

 

[Ben99GT]

Originally Posted By: frmtbiker
Originally Posted By: d00df00d
They might be the same grade, but remember that each grade represents a small range of viscosities.


Right, OK, same grades (5w30)... I was under the impression grade and viscosity were the same.


Not necessarily...

http://www.bobistheoilguy.com/visc.html

30-weight oils can range from 9.3 cSt to 12.49 cSt, so there can be a pretty big difference between two different 30 weight oils.

Take German Castrol 0w30 (not far off of SAE 40-weight viscosity range) and Castrol Edge 5w30 (not far off of SAE 20-weight viscosity range), for instance.

 

[frmtbiker]

Ok, so are the viscosities for different 5w30 weight oils listed? I want to compare Castrol GTX (my last oil changes) and Valvoline Synpower (my current oil). I'm guessing the GTX has a higher viscosity this higher viscosity is what seems to 'cushion' the engines internals.

 

[Ben99GT]

Castrol GTX 5w30
Viscosity @ 40 degrees C - 62.1 cSt
Viscosity @ 100 degrees C - 10.8 cSt

Valvoline SynPower 5w30
Viscosity @ 40 degrees C - 59 cSt
Viscosity @ 100 degrees C - 10.5 cSt

In other words, pretty much a wash...

Mobil 1 5w30 gets many complaints for making engines noisier.

Mobil 1 5w30
Viscosity @ 40 degrees C - 64.8 cSt
Viscosity @ 100 degrees C - 11.3 cSt

Red Line is generally regarded as making engines quieter.

Red Line 5w30
Viscosity @ 40 degrees C - 62 cSt
Viscosity @ 100 degrees C - 10.6 cSt

Clearly there is more than kinematic viscosity contributing to certain oils quieting engines down. I would bring up HTHS viscosity, but even Group III/IV synthetics usually edge out their dino counterparts there.

 

[SLCraig]

I can't say that I've ever come to that conclusion myself, but I gotta say, my Maxima runs freakin' great on Valvoline white bottle.

In the drive thru getting my coffee the other day noticed just how silent it was right up against the wall. Runs great on this oil.

 

[frmtbiker]

Thank you Ben...

SLCraig- This is exactly what I'm talking about. It's times like that when I also notice my 3RZ is running quieter and smoother on conventional oil.