Difference in XW-30s

[1JZ_E46]

Originally Posted By: Ruby2013Elantra
I know, I'm sorry. Just a curious question I had.


No need to be sorry. There’s just a lot of opinions on this forum. Many are unfounded and provided as fact, unfortunately. Sure there is a difference between 0W and 5W oils, but how that translates into real world performance... it’s anyones guess; toss a coin. Many will try to claim one is far better than the other and vice versa, but again, that’s just opinion.

 

[JLTD]

Originally Posted By: ARCOgraphite
I'M running a 10w30 and the engine runs better than any 0w or 5w30 Ive run (for the way I drive, sometimes having to floor it and rev it to 5500 rpm when commuting - only where required, of course)

Why? because its just a magically good oil formulation and they don't come along too often.

Two years ago it was the darling Semisyn Magnatec 5w30 promo oil - A good oil. Then BP spoiled the formula with the FULL Synthetic Formula - BOO!

Before that I was hapless. Desperate.

Five to Seven years ago Edge Gold bottle premium "synthetic" was a top performer, Then BP messed THAT sweet mix up! BOO!


Age old advice?
Above -15F? forget the winter rating and use a GOOD oil. And a good filter.

Now you have to find one. Ain't been an easy road, pardner.




Winter too in NH? Considering the same for the 4Runner.

 

[MoreCowbellAz]

Originally Posted By: rideahorse
Why on earth would anyone run a 0w oil if it is above 0* F


I probably have a different spin on it, but I run Mobil 1 AFE 0w30 year round in all my cars here in Phoenix. I know the 0w spec is irrelevant here but I use it because I tried it years ago in my Prius and noticed it was nice and quiet so started using it in my other cars too with the same result. So even tho the 0w part is completely unnecessary, this oil just works and is a good go-to standard. Oh..............and I can get it for $2.18 per quart after rebate. So no reason to over-think it.

 

[ZeeOSix]

Originally Posted By: rideahorse
Why on earth would anyone run a 0w oil if it is above 0* F


Because 0W is still thicker than any weight oil when it's hot. What if an oil was always around 9~12 cSt (centistokes) no matter what the oil temperature was ...

 

[SilverFusion2010]

Originally Posted By: ZeeOSix
Originally Posted By: rideahorse
Why on earth would anyone run a 0w oil if it is above 0* F


Because 0W is still thicker than any weight oil when it's hot. What if an oil was always around 9~12 cSt (centistokes) no matter what the oil temperature was ...

Unicorn tears?

 

[NGRhodes]

Originally Posted By: SilverFusion2010
Originally Posted By: ZeeOSix
Originally Posted By: rideahorse
Why on earth would anyone run a 0w oil if it is above 0* F


Because 0W is still thicker than any weight oil when it's hot. What if an oil was always around 9~12 cSt (centistokes) no matter what the oil temperature was ...

Unicorn tears?


Viscosity index of 1200

 

[Shannow]

Originally Posted By: ZeeOSix
Originally Posted By: rideahorse
Why on earth would anyone run a 0w oil if it is above 0* F


Because 0W is still thicker than any weight oil when it's hot. What if an oil was always around 9~12 cSt (centistokes) no matter what the oil temperature was ...

Your engine would be destroyed before it warmed up.

The boundary lubricated areas are hydrodynamic with cold thick oil, then the oil thins, and additives come into play.

Sequence IVA is the wear test in the industry, and purposely keeps the temperature in the 60-70C range which is the "sweet spot" for warmup wear to occur.

On of the oil formulators on the site has stated that if they do the same test at a lower temperature (more viscosity), or a higher temperature (better additive activation) they get better wear results.

AS I've said before...if oil viscosity was to remain constant, you would need a broad spectrum AW additive package that worked from -40C.

 

[NGRhodes]

Originally Posted By: Shannow
The boundary lubricated areas are hydrodynamic with cold thick oil


What is the relationship with thickness and wear here, is it linear, drops off a cliff or something else, is there an example of where an oil was too thin cold (for wear protection in the 60-70C range) ?

 

[ZeeOSix]

Originally Posted By: Shannow
Originally Posted By: ZeeOSix
Originally Posted By: rideahorse
Why on earth would anyone run a 0w oil if it is above 0* F


Because 0W is still thicker than any weight oil when it's hot. What if an oil was always around 9~12 cSt (centistokes) no matter what the oil temperature was ...

Your engine would be destroyed before it warmed up.

The boundary lubricated areas are hydrodynamic with cold thick oil, then the oil thins, and additives come into play.

Sequence IVA is the wear test in the industry, and purposely keeps the temperature in the 60-70C range which is the "sweet spot" for warmup wear to occur.

On of the oil formulators on the site has stated that if they do the same test at a lower temperature (more viscosity), or a higher temperature (better additive activation) they get better wear results.

AS I've said before...if oil viscosity was to remain constant, you would need a broad spectrum AW additive package that worked from -40C.


Why wouldn't boundry lubricated areas and hydrodynamic lubrication exist with cold oil at 12 cSt vs hot oil at 12 cSt?

So you're saying with thin hot oil that wear control is mostly due to anti-wear additives on boundry lubricated areas than the oil film thickness?

 

[SilverFusion2010]

He’s saying that the metal on metal areas, let’s use rocker arms or flat tappets, are hydrodynamic when cold because the viscosity of the oil is much higher when cold. ( I don’t agree with his argument, but that’s what he’s suggesting)

Then as the engine warms and the oil thins out these areas transition into mixed and boundary lubrication, where the additives play the primary role in reducing wear. So if you had “hot” viscosity oil in a cold engine, you wouldn’t get the hydrodynamic lubrication in those “hot” boundary wear area and because the additives aren’t active at -40 the engine would destroy itself.

Again, I don’t agree with this, but that’s the argument being presented.

I think that any engine that’s not brand new will have some anti wear film or plating built up on those boundary lubrication areas, and I don’t think that they become hydrodynamic when cold. Mixed maybe.

 

[ZeeOSix]

Originally Posted By: Shannow
The boundary lubricated areas are hydrodynamic with cold thick oil, then the oil thins, and additives come into play.


So does that mean a thicker oil when cold will give more cold start-up wear protection because of better hydrodynamic lubrication in boundry lubricated areas; ie, 10w30 gives more cold running protection than 5w30?

Originally Posted By: Shannow
Sequence IVA is the wear test in the industry, and purposely keeps the temperature in the 60-70C range which is the "sweet spot" for warmup wear to occur.

On of the oil formulators on the site has stated that if they do the same test at a lower temperature (more viscosity), or a higher temperature (better additive activation) they get better wear results.


So that would say over cooling oil well below the 100 C point with some kind of heat exchanger wouldn't be an ideal thing to do.

Do these AW additives just keep on working better and better as the oil temp keeps going up? The HTHS protection gives out before the AW additives?

 

[SilverFusion2010]

Do you have a link to a study where they found cold oil changes boundary lubrication areas to hydrodynamic? I’m trying to visualize it and it’s not working for me, seems like a cam lobe would wipe the film off the wear surface every rotation. There’s no oil pressure on those splash lubed parts that would force them apart and keep them in the hydrodynamic region.

 

[Shannow]

Originally Posted By: SilverFusion2010
Do you have a link to a study where they found cold oil changes boundary lubrication areas to hydrodynamic? I’m trying to visualize it and it’s not working for me, seems like a cam lobe would wipe the film off the wear surface every rotation. There’s no oil pressure on those splash lubed parts that would force them apart and keep them in the hydrodynamic region.


That's why you don't get my point.

HYDROSTATIC lubrication is where oil pressure keeps things apart, and it's very rare to see (turbines use it to lift the shaft for run-u.

HYDRODYNAMIC is where the two relative shaft movements keep dragging oil into the gap which creates the HYDRODYNAMIC pressures to keep the parts separated.

Like a water skier doesn't need water injected between the ski and the water to keep him up.

Get across those facts, and then try to go back over what I'm saying.

bobbydavro has tested the sequence IVA at both colder, and hotter temperatures than the standard and sees lower wear when run colder (more viscosity), and hotter (more additive activation).

 

[Shannow]

Originally Posted By: ZeeOSix
Originally Posted By: Shannow
The boundary lubricated areas are hydrodynamic with cold thick oil, then the oil thins, and additives come into play.


So does that mean a thicker oil when cold will give more cold start-up wear protection because of better hydrodynamic lubrication in boundry lubricated areas; ie, 10w30 gives more cold running protection than 5w30?

Originally Posted By: Shannow
Sequence IVA is the wear test in the industry, and purposely keeps the temperature in the 60-70C range which is the "sweet spot" for warmup wear to occur.

On of the oil formulators on the site has stated that if they do the same test at a lower temperature (more viscosity), or a higher temperature (better additive activation) they get better wear results.


So that would say over cooling oil well below the 100 C point with some kind of heat exchanger wouldn't be an ideal thing to do.

Do these AW additives just keep on working better and better as the oil temp keeps going up? The HTHS protection gives out before the AW additives?


https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3680194/1

Here's a thread I started ages ago on the topic.

bobbydavro's comments are on page 2 (my page 2)

 

[SilverFusion2010]

The water ski comparison made things clear. Thanks.

 

[Shannow]

 

[cheesepuffs]

Originally Posted By: Shannow
Originally Posted By: SilverFusion2010
Do you have a link to a study where they found cold oil changes boundary lubrication areas to hydrodynamic? I’m trying to visualize it and it’s not working for me, seems like a cam lobe would wipe the film off the wear surface every rotation. There’s no oil pressure on those splash lubed parts that would force them apart and keep them in the hydrodynamic region.


That's why you don't get my point.

HYDROSTATIC lubrication is where oil pressure keeps things apart, and it's very rare to see (turbines use it to lift the shaft for run-u.

HYDRODYNAMIC is where the two relative shaft movements keep dragging oil into the gap which creates the HYDRODYNAMIC pressures to keep the parts separated.

Like a water skier doesn't need water injected between the ski and the water to keep him up.

Get across those facts, and then try to go back over what I'm saying.

bobbydavro has tested the sequence IVA at both colder, and hotter temperatures than the standard and sees lower wear when run colder (more viscosity), and hotter (more additive activation).


I thought oil pressure or hydrostatic was what ever bearing in an engine used? Making it extremely common.

 

[Shannow]

Originally Posted By: cheesepuffs
I thought oil pressure or hydrostatic was what ever bearing in an engine used? Making it extremely common.


Oil pressure is there to get the oil to the bearing, not to provide "lift"

Think about it logically, the oil ports are pressing AGAINST the loaded side of the bearing.

The oil is "stuck" to both the shaft and the bearing, and as the gap gets smaller, the pressure generatted by the oil film goes up.