OW-16 vs 0W-20 viscosity specs - does it really matter.

[Jetronic]

No, that's not how that oil pump works. It's not a computer fan.

yes it does, actuator with pwm control varies the volume being pumped to meet a pressure target. No matter how you dress it up, that's what it does.

Variable Displacement: The Future of the Oil Pump is Here – UnderhoodService

Variable displacement oil pumps control how hard the pump works by matching the pressure and volume to engine temperature, loads and engine speeds.

www.underhoodservice.com

Pump​

Almost every variable displacement oil pump application is mounted on the crankshaft. This placement eliminates the need for an intermediary shaft that can fail.


Variable displacement pumps are “gerotor” designs. Gerotor pumps have trochoid gears that allow for smooth operation, low noise and excellent suction. The centrically seated drive gear drives an external eccentrically seated annular gear. The result of which is cavities inside the pump compress and enlarge to create the suction and feed effect.


The inner rotor sits on the crankshaft and drives the outer rotor. Since the inner and outer rotors have different rotating axes, more space is created on the suction side due to the rotating motion. The oil is drawn in and transported to the pressure side. On the pressure side, the space between the gears’ teeth becomes smaller again, and oil is forced into the oil circuit under pressure.


A variable displacement oil pump changes the rotating axis of the outer gear. To achieve this, the gears of the inner rotor are replaced with variable-length vanes. The outer gear pivots on an axis; opposite the pivot is an electronic actuator. On mechanical versions, a spring replaces the actuator and the opposite side of the housing has oil or a piston that pushes against the spring to regulate pressure.

Actuator​

Most variable displacement oil pumps use an electric solenoid to change the axis and eccentricity of the pump housing, and position is determined by the ECM. Changing the geometry of the housing changes the amount of pressure and volume of the pump. Most actuators use a pulse width modulated signal to control the position of the actuator, and some scan tools can display the PID for the actuator position.

 

[ATex7239]

If you plan on going to the track, towing, or it’s currently 120F where you’re at then yeah change it. If you’re just doing run of the mill daily commuting and the temp is mild then it’s fine to leave it.

And it’s a PD oil pump. The pressure is electronically controlled like numerous others engines out there. This isn’t anything special folks. The ECM is clearly capable of maintaining pressure regardless as multiple grades are allowed and viscosity will change substantially based on many factors. That is why we have multi-grades folks. I’m fairly sure Toyota engineers know this fact. The “it’s programmed for 0w16” notion is bunk.

Toyota Dynamic Force four-cylinder “electronic” oil pump

I saw this topic came up again recently. I recall a long thread last year that I thought put this to bed. But I guess not. The electronic oil pump speculation appears to be based on a video by the Car Care Nut saying the oil pump was electronic and calibrated for 0w-16. This being the reason for...

bobistheoilguy.com

 

[PimTac]

If you plan on going to the track, towing, or it’s currently 120F where you’re at then yeah change it. If you’re just doing run of the mill daily commuting and the temp is mild then it’s fine to leave it.

I suspect that this vehicle is not one normally taken to a track. Everything else can be handled well with the 0W-16.

 

[FZ1]

What instigated this thread is I am debating dumping the new 0W-16 out of my Toyota and replacing it with 0W-20. The 0W-16 is new. I took the car to the dealer - feel obligated as its still in warranty - and they changed the oil for free - work order and window sticker say 0w-16 which is what the manual calls for.

In reviewing the J300 specs, there is quite a bit of overlap in the spec, and HTHS isn't that far apart?

I also have no idea what they put in - likely the cheapest crap around. However in looking at the M1 Advanced Fuel Economy for the 16 vs 20 weight, there like 7.2 Vs 8.2 [email protected]?

So do I dump it and put in 0w-20?

Side question, if I do - do I change the filter - its a new OEM filter - so I am thinking not on that part.


View attachment 137054

What does the oil cap say. 0-16 or 0-20?

 

[SC Maintenance]

What does the oil cap say. 0-16 or 0-20?

The oil cap says Nothing.

The manual says 0w-16 recommended, but 0w-20 can be used.

 

[Rod Knock]

yes it does, actuator with pwm control varies the volume being pumped to meet a pressure target. No matter how you dress it up, that's what it does.

Variable Displacement: The Future of the Oil Pump is Here – UnderhoodService

Variable displacement oil pumps control how hard the pump works by matching the pressure and volume to engine temperature, loads and engine speeds.

www.underhoodservice.com

I have one of these pumps in the 3.3L GDI Lambda II engine in my 2017 Hyundai Santa Fe SE. It's a 300HP engine, and I love driving this thing, with a heavy foot. This engine has the same VVP style oil pump. The owner's manual allows anything up to 20W-50. In some European countries like Germany the Grand Santa Fe (same vehicle) is sold with this engine and calls for 0W-20. The factory fill is Shell Helix Ultra 5W-40. I run Mobil 1 FS 0W-40 in it.

*It allows up to 5W-40 in the Owner's Manual and up to 20W-50 in the Service Manual.

Here is an old animation from back when this engine was first introduced:



The PUG 3.6L V6 MPI engine in my 2022 Dodge Durango has a two-stage VVP pump. I upgraded the oil in this engine and it works perfectly fine.

Positive Displacement (PD) oil pumps are not as sensitive to viscosity as you may think, unless they are worn out. And when they wear out, they have trouble pushing low viscosity oils. While most engines can infer viscosity from oil temperature, outside temperature, and coolant temperature, like the 5.7 HEMI does, which ironically has an old school PD gear pump... most engines don't act on it. Also, ironically, the 5.7 HEMI will slow down VVT actuation if it finds the oil to be higher than around 14~15 cSt, which in turn can negatively affect fuel economy.

However, no, the ECM will not nuke an engine because you're running 0W-20 instead of 0W-16. Now, it you jump up to a 0W-40 or 5W-40, then you might be able to tell a difference, usually manifesting itself as a loss in fuel economy.

"Setting codes" has more to do with the car manufacturer's obligation to force the owner to use the oil viscosity that they used to qualify their fuel economy numbers. For the life of me, I can't attain the advertised 25 Highway MPG in my 2022 Durango no matter what. Going to 5W-30 hasn't impacted my fuel economy in any negative way either. Oh, if I drive 60 ~ 65 MPH on a flat piece of road, then sure, I get the 25MPG.

Though most car manufacturers don't want to upset their customers, especially when said customers are other companies or law enforcement agencies, so they don't do much of the "setting codes" stuff, mostly because fleets that are "used & abused" don't run the recommended low viscosity oil.

I hope this settles it.

 

[Jackson_Slugger]

Isn't the engine specifically designed to run on 0W-16 using special materials/coatings?

 

[Jetronic]

I have one of these pumps in the 3.3L GDI Lambda II engine in my 2017 Hyundai Santa Fe SE. It's a 300HP engine, and I love driving this thing, with a heavy foot. This engine has the same VVP style oil pump. The owner's manual allows anything up to 20W-50. In some European countries like Germany the Grand Santa Fe (same vehicle) is sold with this engine and calls for 0W-20. The factory fill is Shell Helix Ultra 5W-40. I run Mobil 1 FS 0W-40 in it.

*It allows up to 5W-40 in the Owner's Manual and up to 20W-50 in the Service Manual.

Here is an old animation from back when this engine was first introduced:



The PUG 3.6L V6 MPI engine in my 2022 Dodge Durango has a two-stage VVP pump. I upgraded the oil in this engine and it works perfectly fine.

Positive Displacement (PD) oil pumps are not as sensitive to viscosity as you may think, unless they are worn out. And when they wear out, they have trouble pushing low viscosity oils. While most engines can infer viscosity from oil temperature, outside temperature, and coolant temperature, like the 5.7 HEMI does, which ironically has an old school PD gear pump... most engines don't act on it. Also, ironically, the 5.7 HEMI will slow down VVT actuation if it finds the oil to be higher than around 14~15 cSt, which in turn can negatively affect fuel economy.

However, no, the ECM will not nuke an engine because you're running 0W-20 instead of 0W-16. Now, it you jump up to a 0W-40 or 5W-40, then you might be able to tell a difference, usually manifesting itself as a loss in fuel economy.

"Setting codes" has more to do with the car manufacturer's obligation to force the owner to use the oil viscosity that they used to qualify their fuel economy numbers. For the life of me, I can't attain the advertised 25 Highway MPG in my 2022 Durango no matter what. Going to 5W-30 hasn't impacted my fuel economy in any negative way either. Oh, if I drive 60 ~ 65 MPH on a flat piece of road, then sure, I get the 25MPG.

Though most car manufacturers don't want to upset their customers, especially when said customers are other companies or law enforcement agencies, so they don't do much of the "setting codes" stuff, mostly because fleets that are "used & abused" don't run the recommended low viscosity oil.

I hope this settles it.

Actually, I meant they don't care about viscosity, not sure what made you think otherwise

 

[Rod Knock]

Isn't the engine specifically designed to run on 0W-16 using special materials/coatings?

Tolerances haven't changed in decades.

It has a multi-stage VVP oil pump. Still, it can't compensate for when you use 0W-16 while towing something at the limit "in the mountains".

Those "special coatings" wear off as the engine ages/wears, so you can't rely on them forever. Now, how "cool" is that? I also like the marketing term "High Mileage" oil. These products exist for a reason.

Actually, I meant they don't care about viscosity, not sure what made you think otherwise

Then you might want to read the article you linked.

 

[Jackson_Slugger]

Tolerances haven't changed in decades.

It has a multi-stage VVP oil pump. Still, it can't compensate for when you use 0W-16 while towing something at the limit "in the mountains".

Those "special coatings" wear off as the engine ages/wears, so you can't rely on them forever. Now, how "cool" is that? I also like the marketing term "High Mileage" oil. These products exist for a reason.


Then you might want to read the article you linked.

I didn't say anything about "tolerances" nor the pump, so please keep your strawman in check. Though obviously engine design and fit-and-finish have greatly improved, although other issues like GDI have arisen. But I love your speculation though regarding coatings wearing off. I wish I could be so certain about narratives that fit my preexisting biases...

Also guessing they'll be a HM 0W-16 MaxLife soon...

 

[Jetronic]

Then you might want to read the article you linked.

Variable displacement oil pumps control how hard the pump works by matching the pressure and volume to the conditions. These conditions can include engine temperature, loads and engine speeds.

hat means, volume is reduced when a set pressure is exceeded.

The pressure that the pump tries to achieve depends on load, engine speeds and temperature, but SAE viscosity doesn't matter, in that volume is increased if pressure is lower (due to viscosity or any other reason)

 

[Rod Knock]

I didn't say anything about "tolerances" nor the pump

You implied. See here:

Isn't the engine specifically designed to run on 0W-16

issues like GDI have arisen

Since when is GDI an issue? Now, how it's implemented and how each owner takes care of their vehicle, that's a different story. Then again, I've seen carboned up MPI engines that also have fuel dilution issues and their intake valves look disgusting.

But I love your speculation though regarding coatings wearing off.

Here's a quick example. I'm sure you can find more on your own if you search:

 

[Rod Knock]

Actually, I meant they don't care about viscosity, not sure what made you think otherwise

The pressure that the pump tries to achieve depends on load, engine speeds and temperature, but SAE viscosity doesn't matter, in that volume is increased if pressure is lower (due to viscosity or any other reason)

From your article:

I'm just reposting what you linked. I didn't say you said or implied the above.

 

[Jetronic]

I have never seen it happen though, and we ran 5W-40 in our vehicles that run 5W-20 in the US.... can't be very sensitive to that. Also, oils thicken from oxidation, thin from shearing, thin from fuel dilution except if it's diesels then the oil can thicken when it's cold enough.....

Never ever one issue, except for actuators stuck from soot buildup on extremely long drain intervals

 

[SubieRubyRoo]

Does the ECU controlled oil pump care? Probably.

Please explain how it could care (or tell)? All it’s doing is matching the requested pressure.

 

[Rod Knock]

I have never seen it happen though, and we ran 5W-40 in our vehicles that run 5W-20 in the US.... can't be very sensitive to that. Also, oils thicken from oxidation, thin from shearing, thin from fuel dilution except if it's diesels then the oil can thicken when it's cold enough.....

Never ever one issue, except for actuators stuck from soot buildup on extremely long drain intervals

I haven't had viscosity related issues either. Craziest experiment I did was to add a quart of Lucas to about 5 quarts of Castrol GTX 20W-50... back in 2004, in my wimpy 2.4L Mitsubishi engine. I had a 1997 beater Mitsubishi Galant back then and thought it would be a fun thing to try during the summer. I was about to do a timing belt and water pump job anyway, so I said why not? Nothing happened, the engine ran just fine. Oh, the water pump completely failed the next day while I was driving around, it was a Sunday. I replaced it, and the timing belt, and ran Rotella 15W-40 in it until I sold it. Good times, lol.

 

[kschachn]

Isn't the engine specifically designed to run on 0W-16 using special materials/coatings?

No engine is “designed” to run a grade. An engine can be designed to tolerate thinner grades of oil, but that in no way precludes the use of one that is thicker. Any engine would be destroyed in short order if this were the case.

MOFT protects not harms. The reverse is not true.

 

[kschachn]

I have never seen it happen though, and we ran 5W-40 in our vehicles that run 5W-20 in the US.... can't be very sensitive to that. Also, oils thicken from oxidation, thin from shearing, thin from fuel dilution except if it's diesels then the oil can thicken when it's cold enough.....

Never ever one issue, except for actuators stuck from soot buildup on extremely long drain intervals

Plus here in the upper Midwest many engines never reach their designed operating temperature on some days. It would be the end of all of those engines if they were so poorly designed they could not tolerate different viscosities.

 

[Jimmy_Russells]

Nobody ever discusses temperature in these debates. Even 10° makes a big difference. I think most people would be surprised to know that if a 0w16 vehicle usually is around 200° the oil is thicker at operating temp than another car using 0w20 at 210°.

 

[hemioiler]

Nobody ever discusses temperature in these debates. Even 10° makes a big difference. I think most people would be surprised to know that if a 0w16 vehicle usually is around 200° the oil is thicker at operating temp than another car using 0w20 at 210°.

Exactly. That's why I can accept the argument that 1 thicker weight is no problem at all; the engine sees greater viscosity ranges in Canada/Alaska where temps can range from -40 F to towing at 250+ F.