Thicker Oil and Variable Valve Timing

[Astro14]

Originally Posted by Bullwinkle007
If your engine is consuming oil stay away from 0 wt. Run a 5/40


How does the first number in an oil viscosity specification affect the oil consumption?

Put differently, why would a 0W30 have higher consumption than a 10W30?

 

[AJB0009]

This has been a concern of mine as well. I finally jumped though and put 5W30 EDGE in my 12 Fusion 2.5L with VVT that has always run 5W20 MC SB in it.
I did notice that the valvetrain clatter that has always been there did quite down a quite a bit. It is still there, but much more faint now.
I haven't driven it much yet since the change, may be a 100 miles or so. No issues yet. Other than the valvetrain noise quieting down some, I haven't noticed any other changes.
I track fuel mileage each fill up, so I'll see if there is any change there.

 

[KCJeep]

Originally Posted by AJB0009
This has been a concern of mine as well. I finally jumped though and put 5W30 EDGE in my 12 Fusion 2.5L with VVT that has always run 5W20 MC SB in it.
I did notice that the valvetrain clatter that has always been there did quite down a quite a bit. It is still there, but much more faint now.
I haven't driven it much yet since the change, may be a 100 miles or so. No issues yet. Other than the valvetrain noise quieting down some, I haven't noticed any other changes.
I track fuel mileage each fill up, so I'll see if there is any change there.


Try Magnatec 5w30 next time it might just go away altogether.

 

[JosephH1]

Well, the dealer is doing an oil consumption test now. They changed the oil, removed my Fumoto valve and marked the new drain plug. I will go back in 1,200 miles and see how much this engine consumed. Yes, I checked to make sure they did not overfill!

 

[Sayonara_Sonata]

If a variable valvetrain is hydraulically driven a performance hit will be felt twixt 5w-30 & 5w-40.

 

[OVERKILL]

If a variable valvetrain is hydraulically driven a performance hit will be felt twixt 5w-30 & 5w-40.

You realize temperature has a far greater impact on viscosity than the grade on the bottle, right? BMW spec'd everything from 0w-30 to 10w-60 for the same VANOS components, Ford has spec'd everything from 5w-20 to 5w-50 for the same VCT components and FCA has spec'd everything from 5w-20 to 0w-40 for the same VCT and MDS components. Engines cannot employ systems that are hyper-sensitive to viscosity because of the fact that viscosity is hyper-sensitive to temperature. When an oil is thousands of cP at -10C, hundreds of cP on a warm start and then in the single digits at operating temperature, assuming it gets there, absolutely necessitates systems that are broadly tolerant.

 

[Sayonara_Sonata]

I know a 2.0T hydraulic CVVT, intake & exhaust, feels the dif running 5W-40. Takes 200-250 miles to knock the green off and on a 5K OC it runs as a scalded ape the last 500-1500 miles.

 

[OVERKILL]

I know a 2.0T hydraulic CVVT, intake & exhaust, feels the dif running 5W-40. Takes 200-250 miles to knock the green off and on a 5K OC it runs as a scalded ape the last 500-1500 miles.

That's hardly a compelling scientific study of operation, nor is it qualified by any sort of viscosity data validating a change in viscosity. Have you done oil analysis at these mileage points to actually measure if there is any change? Do you track oil temperature and oil pressure?

 

[Zaedock]

We've never noticed a perceptible power difference between a 30 grade and 40 grade in our 2.0T.

 

[Sayonara_Sonata]

Scientifically compelling eh? What, was you planning on paying me for my opinion?

I merely shared my experience. There's parasitic drag on the internals though over the decades of driving various vehicles I've never run across as much as I feel with this auto. That leaves the turbo and the actuators as this is the only auto I've owned that came so equipped.

The exhaust CVVT alone, Vs none, on this engine is good for 25HP. The intake CVVT plays an even greater role hence early engines having only intake camshaft VVT.

This style of the YF was used for a few years. Then the hydraulic VV intake was upgraded to electrically operated. This allowed more manipulation as they could now incorporate the intake into the mapping electrically. And perhaps help discourage the use of 5w-20. Which was somewhat en vogue in the early years by individuals and dealerships alike.

I do not know if your 2016 Kia 2.0T has the same hydraulic camshaft actuators.

I know a fellow that drag races. He turns 3 sec flat 60'. He dynoed his engine with his preferred Valvoline 15W-50. Then he drained it replacing with 30. Found a whopping six HP. He drained it and replaced the 30 with 15W-50.

Parasitic drag from heavier oil isn't much.

That leaves the turbo and/or the hydraulic camshaft actuators. One or the other or both.

I choose the later...

Why?

 

[OVERKILL]

Scientifically compelling eh? What, was you planning on paying me for my opinion?

I merely shared my experience. There's parasitic drag on the internals though over the decades of driving various vehicles I've never run across as much as I feel with this auto. That leaves the turbo and the actuators as this is the only auto I've owned that came so equipped.

The exhaust CVVT alone, Vs none, on this engine is good for 25HP. The intake CVVT plays an even greater role hence early engines having only intake camshaft VVT.

This style of the YF was used for a few years. Then the hydraulic VV intake was upgraded to electrically operated. This allowed more manipulation as they could now incorporate the intake into the mapping electrically. And perhaps help discourage the use of 5w-20. Which was somewhat en vogue in the early years by individuals and dealerships alike.

I do not know if your 2016 Kia 2.0T has the same hydraulic camshaft actuators.

I know a fellow that drag races. He turns 3 sec flat 60'. He dynoed his engine with his preferred Valvoline 15W-50. Then he drained it replacing with 30. Found a whopping six HP. He drained it and replaced the 30 with 15W-50.

Parasitic drag from heavier oil isn't much.

That leaves the turbo and/or the hydraulic camshaft actuators. One or the other or both.

I choose the later...

Why?

Well, you revived a thread that had been dormant for three months to insert your opinion, so I figured I'd address it with some facts. The point is that the difference between visc on the bottle at temp is VERY small relative to the impact temperature has on it.

Let's use some data points to illustrate here, just for fun.

Two oils, your 5w-40 and a ILSAC 5w-30, to give us the biggest difference, since a Euro 5w-30 will be far closer to our 5w-40 viscosity-wise.

1. Mobil 1 Formula M 5w-40
40C Visc: 79cSt
100C Visc: 13.2cSt

2. Mobil 1 5w-30
40C Visc: 62cSt
100C Visc: 11.1cSt

So, if both oils at are temp, we are looking at a difference of just 2.1cSt, but look at how that grows and how much viscosity increases as the temperature drops.
At just 10C cooler (90C) our 5w-30 is heavier than our 5w-40, having a visc of 13.8cSt. This is why I asked of you tracked oil temperature. Conversely, at just 108C, our 5w-40 is the same visc as our 5w-30 at 100C.

In a vehicle without a coolant/oil heat exchanger, oil temp will be all over the map. Ambient temp can have a significant impact on it, and thus viscosity. Load and RPM also can rapidly change oil temperature. On the other hand, in an engine with a coolant/oil heat exchanger, you are keeping the oil very close to coolant temperature where the viscosity difference is quite small.

 

[Zaedock]

Excellent post.

 

[Hogwash]

Since it's been revived.....got a buddy that has a Scion FR-S. It's both his DD and autox rig. He has beat the piss out of that thing for 7 years. It's seen M1 0/40 it's entire life.....spec'd for 0/20.

That's seems like solid proof that 0/40 is fine in a Subaru engine IMO

 

[Cujet]

There are very few engines that have operational issues with higher viscosity. Use it with confidence. It's good to note that the viscosity of "cool oil" such as during cold weather operations or just before fully warmed up, is far, far, far higher than the operational viscosity of a more viscous oil that's fully warmed up.

 

[Sayonara_Sonata]

Let us for argument's sake assume my perception and conclusion of noticable acceleration loss, across the full RPM betwixt differing OC, is valid. As the ending of Casa Blanca we'll round up the usual suspects. The additional parasitic loss of 5W-40 compared to 5W-30, the same for the turbo and the function of the hydraulic camshaft actuators.

I employed the 5-40 for over 30K miles consecutively. I live in a temperate climate producing short mild winters with lengthier mild to hot summers. Usage of the 5W-40 spanned a couple of years. It was Rotella T6 an oil tailored exclusively for diesel engines. However, I experienced the much the same degradation of power, after a few OCs of 5W-30, with M1 euro FS 0W-40 as well. To wit, a pattern.

I keep me foot in 'er arse and pay no attention to MPG. I've noticed similiar results in NA engines, but not to this extent. So, I conclude additional parasitic friction loss of the engine internals along with the turbo as being secondary in the combined loss.

I feel the camshafts hydraulic movement via the actuators bears the lion's share of loss. I contend their movement by 5W-40 and/or 0W-40, both in comparission to 5W-30, is sluggish and as a result a greater power lose when contrasted unto parasitic friction. They all combine for a total loss though not neccessarily in equal amounts.

You certainly are welcome to your opinion.

 

[PimTac]

“I feel the camshafts hydraulic movement via the actuators bears the lion's share of loss.”


I am going to wait for a engineer to explain this one.

 

[Sayonara_Sonata]

The YF Theta II has an intercooler for the turbo but, no such external cooling for the oil. The engine bay stays hot in part due to the bonnet lining and turbo though the largest factor is lack of adequate volume of outside air. I noted that the new models come with huge grilles. It has long been my contention that they sacrificed adequate cooling for aesthetics.

I enjoy applied science. Me butt plied to the bucket. The T6 5-40 OC were predictable und repeatable. After a few OC it became ho-hum. It is the difference in T6 5W-40 compared to various 5W-30 oils being exaggerated by the movement of VVT in this instance in terms of rates of acceleration. The only component in this equation capable of multiplying that effect; detectable via G force exerted on said butt. The timing of the hydraulic camshaft actuators being influenced by the different characteristics betwixt the two oils mentioned.

Does not scientifically confirm the notion correct though that is what I deduce. Point somewhat moot as several years ago, as previously mentioned, the hydraulic intake actuator was upgraded to electric solenoid. The lesser influential exhaust as Led Zeppelin's song, remains the same...

 

[Craig in Canada]

I've generally observed that on VVT systems with wear, higher viscosity or HTHS improves operation and provides more performance. Specifically, it restores closer to as-designed performance to a worn system.

My sample space is admittedly small - a couple of Toyota 2GR-FE, BMW M52. My theory: if there's leakage in the seals the VVT system is is slower to respond or less able to build the forces necessary to adjust the timing without requiring more oil pressure/flow (engine rpm) or time than originally designed.

Less leaking -> higher actuator force with less oil pressure -> VVT responds as originally designed -> original performance.

On my BMW M52 part throttle mid-rpm performance was higher when the oil was not quite all the way warmed up or when thicker oils were chosen. Replacing the VANOS seals made it consistently perform at the higher (originally designed) level even on thinner/hot oil.

On 2GR-FE, moved from the recommended EDGE 0W20/5W20 to EDGE 0W40 (Euro) for one OCI. Significantly increased performance by butt dyno observed immediately and throughout the OCI compared to either 20 grade. This engine didn't consume oil, so I think the performance increase was not ring seal, but VVT. VVTi startup clatter also seemed improved. Drop in mpg due to high HTHS was not noticeable in practical use and worth the trade-off overall.

NOTE: I'm referring to a worn system performing closer to original design, not making a like-new system perform better.

 

[demarpaint]

I'm loving the "thicker" 0W30 Mobil 1 ESP in my VVT engine which calls for 5W20 oil. No problems to report, in fact I have a quieter engine as far as I can tell, and good UOA reports moving up a grade. I think there are a lot of myths concerning oil viscosity and VVT engines.

 

[OVERKILL]

I'm loving the "thicker" 0W30 Mobil 1 ESP in my VVT engine which calls for 5W20 oil. No problems to report, in fact I have a quieter engine as far as I can tell, and good UOA reports moving up a grade. I think there are a lot of myths concerning oil viscosity and VVT engines.

After significant experimentation, as I'm sure you recall, I "settled" on M1 AFE 0w-30 in our old 2002 Expedition due to its excellent cold temperature performance (that vehicle saw -30C several times) and zero consumption on 12,000Km OCI's. That was an engine that was originally spec'd for 5w-30 and then back-spec'd to 5w-20 in later years when Ford went 5w-20 almost universally across the board. I have no idea what the current owner is putting in it, but I did tell him what I had been running.

Not only are there a lot of myths concerning VVT, but there are also plenty concerning cylinder deactivation.