0W20 vs 0W30

[ZeeOSix]

I asked the question because I suspect the oil goes through more of a change in viscosity when running your truck from freezing to operating temp, than it does running at operating temp between 0w-30 and 0w-20.

In other words, in order for him to notice the car being less sluggish with a 0w-20 due to a decrease in viscosity, he'd have to notice the same increase in power as his car warms up using the same engine oil.

I doubt anybody could pass a double blind study and feel the difference (in either scenario above). Confirmation bias is probably at play here.

For someone to feel and correlate an engine's "sluggishness" vs oil viscosity during warm-up they would have to know exactly what the oil viscosity was every second as the oil is warming up. It would be very difficult to measure that with accurate test instrumentation, let alone just by someone's mind from what they "feel" while driving a vehicle as the oil warms up. Especially if that was done even just a day apart, let alone a whole OCI apart.

Let's say someone did a WOT dyno test on the same car using xW-20 and wW-30 at full operating temperature an found the xW-20 gave 255 HP instead of 250 HP (2% HP increase - probably being generous here). You think someone could feel a "sluggishness" difference if just cruising around at 50 HP or less ... that means they would have to be able to sense a 1 HP or less power difference from the driver's seat. I say no way that's really accurately possible.

Agree on the double blind study ... doubt that anybody could really even feel the difference at WOT in the driver's seat between 250 and 255 HP output.

 

[4WD]

20 -vs- 30 ?

https://www.bing.com/videos/search?...arch?q=Well+Isn%27t+That+Special+&FORM=HDRSC3

 

[930.engineering]

Agree on the double blind study ... doubt that anybody could really even feel the difference at WOT in the driver's seat between 250 and 255 HP output.

Perhaps. However WOT isn't what actually matters.
You may remember at least one time I told I too feel (or imagine
to feel if you like) a difference in particular on my GTI when I tried
5W-40 after 0W-30. And it matters to me.
.

 

[ZeeOSix]

Perhaps. However WOT isn't what actually matters.
You may remember at least one time I told I too feel (or imagine
to feel if you like) a difference in particular on my GTI when I tried
5W-40 after 0W-30. And it matters to me.
.

Was that way after the oil was fully warmed up to a constant and equal temperature and under the same exact driving conditions, or during the warm-up phase? If the latter, it's possible that some newer cars could change the ECU control of how the engine runs until the oil is above a certain temperature. If the ECU is changing the way it runs, that could be perceived as being "sluggish".

 

[hemioiler]

Funny story. Back in the late 90's I was diagnosing a slow computer for an elderly woman. Typical windows 98 stuff, bloated registry, multiple anti-this-or-that stuff running in the background and way too little horsepower yada yada. So while she was explaining her issue to me I noticed her impatiently tapping her mouse up and down (the whole mouse off/on the mousepad, she was "hitting" the mouse on the mousepad) and after a while I asked her why she was doing that. Her response: "the computer reacts faster". Somehow in her mind the computer was able to detect her impatience. I didn't have the heart to tell her the mouse doesn't have impatience sensors or gyroscopes or earthquake detectors or anything like that. I was just impressed she was using the computer at her age.

Anyway the point is that sometimes coincidence or other variables we haven't properly accounted for, can make us feel one way even though it can't possibly be happening.

 

[930.engineering]

Was that way after the oil was fully warmed up to a constant and equal temperature and under the same exact driving conditions, or during the warm-up phase? If the latter, it's possible that some newer cars could change the ECU control of how the engine runs until the oil is above a certain temperature. If the ECU is changing the way it runs, that could be perceived as being "sluggish".

I understand you, and I am aware of temp/visco. It's some years ago,
however I had that impression several times, even when warm, despite
no huge differences in HTHS and KV @ 100°C. The 0W-30 before has
been Shell Helix Ultra Professional (Pz Platinum Euro LX, VW 504 00)
and then Ravenol RUP 5W-40 (at that time VW 502 00, now 511 00)
after. Yes, the EA888 3G oil pump has an electronically controlled
solenoid (depending on load and RPM, perhaps mediately to temp),
but....
Can make 3.5 vs 3,9 mPas and 11.9 vs 14,3 mm²/s** for a noticeable
difference? It seems to me. I choose to forgo the word 'sluggishness'.

**59 vs 88 mm²/s @ 40°C (104°F)

ps:
Anyway, I'm not in any need. VW allows everything from 0W-20 (VW
508 00) up to 5W-40 (VW 502 00). So with 5W-30 (VW 504 00) I think
I have found my golden mean.
Much more interesting to try different transmission oils. Way more
easy to notice true differences, so far especially on my Mini and my
Porsche.
.

 

[ARCOgraphite]

So you're (or anyone else here) claiming you can feel a 250+ HP engine become more "sluggish" at operating temp because the HTHS viscosity went from 2.6 to 3.2 cP? As mentioned, time for a blind HTHS test, lol.

Who said 250HP? More like 112-175. Mainly in little stick shift buzz bombs. And to answer your question - Yes, without a doubt.

I am AGHAST that you couldn't or haven't. Maybe you haven't done viscosity tailoring.

- Ken

 

[ARCOgraphite]

Not discussing peak loaded torque when resolving " sluggishness" rather dynamic acceleration of hydraulically damped reciprocating components at throttled low cylinder pressures and low-to-moderate rpm operating regime

 

[ARCOgraphite]

Whoa! Tone it down dude!

Nobody want to read that boring thesis!

(said to self)

 

[SubieRubyRoo]

Whoa! Tone it down dude!

Nobody want to read that boring thesis!

(said to self)

“Passion makes people crazy,” she said as she held the pillow over his sleeping face…

 

[ZeeOSix]

Who said 250HP? More like 112-175. Mainly in little stick shift buzz bombs. And to answer your question - Yes, without a doubt.

I am AGHAST that you couldn't or haven't. Maybe you haven't done viscosity tailoring.

- Ken

When I went from 5W-20 to 5W-30 in a Coyote there was zero perceived difference in "sluggishness" of the engine. If I did that in my 5 HP edger and was edging my lawn (engine under load) it might be a different story.

The more HP the engine is putting out, the less noticeable a change in the oil viscosity (with all other factors held constant) is going to be "perceived". Can anyone tell if the engine is "more sluggish" just cruising along at 2~3% throttle opening? Highly doubt it. And in order to tell the increase in engine friction and HP loss due to thicker oil it would have to be ran on an accurate dyno to measure the difference - again, with all other factors held constant while only the oil viscosity was changed.

 

[kschachn]

When I went from 5W-20 to 5W-30 in a Coyote there was zero perceived difference in "sluggishness" of the engine. If I did that in my 5 HP edger and was edging my lawn (engine under load) it might be a different story.

Again, the less HP the engine is putting out, less noticeable a change in the oil viscosity (with all other factors held constant) is going to be "perceived". Can anyone tell if the engine is "more sluggish" just cruising along at 2~3% throttle opening? Highly doubt it. And in order to tell the increase in engine friction and HP loss due to thicker oil it would have to be ran on an accurate dyno to measure the difference - again, with all other factors held constant while only the oil viscosity was changed.

As @CarbonSteel likes to say it was another seagull post.

 

[ChrisD46]

Some engines such as the Hyundai Theta II 2.4L GDI engine have 5W20 / 0W20 stamped on the oil cap but will offer a bit more film strengh / wear protection with a 5W30 or 0W30 oil as rod bearings have been known to be a problem on this engine design . The Hyundai owner manual allows for 0W, 5 and 10W 20 weight as well as same in 30 weight oils of your choice , so in this case running a 0W30 , 5W30 or 10W30 is a better choice.

 

[ARCOgraphite]

When I went from 5W-20 to 5W-30 in a Coyote there was zero perceived difference in "sluggishness" of the engine. If I did that in my 5 HP edger and was edging my lawn (engine under load) it might be a different story.

The more HP the engine is putting out, the less noticeable a change in the oil viscosity (with all other factors held constant) is going to be "perceived". Can anyone tell if the engine is "more sluggish" just cruising along at 2~3% throttle opening? Highly doubt it. And in order to tell the increase in engine friction and HP loss due to thicker oil it would have to be ran on an accurate dyno to measure the difference - again, with all other factors held constant while only the oil viscosity was changed.

That is not surprising in the least If I shoved 5w30 up Coyote's tail I would not expect him to be sluggish!

You just jogged my memory that this surprisingly happened to me - and was first noticed - on a 2001 Bullitt with a manual trans. Many Ford service centers didn't have the 5w20 oil for some reason. I brought it to a local L-M dealer for an oil change. they gave me the car back, check the level and filter, all seem well then I headed off. Promptly I said whoa ! Whats wrong?! I look down at the E brake - that was off. Looked out back for and Airstream trailer - that wasn't there.
There was a quite noticeable dulling of the engine response in normal driving. But a fresh tight engine and new unsheared oil.

As I stated before, I have noticed the effect in many cars and many engines over many years. Very discernable

- Ken

 

[SugarMouth]

For someone to feel and correlate an engine's "sluggishness" vs oil viscosity during warm-up they would have to know exactly what the oil viscosity was every second as the oil is warming up. It would be very difficult to measure that with accurate test instrumentation, let alone just by someone's mind from what they "feel" while driving a vehicle as the oil warms up. Especially if that was done even just a day apart, let alone a whole OCI apart.

Let's say someone did a WOT dyno test on the same car using xW-20 and wW-30 at full operating temperature an found the xW-20 gave 255 HP instead of 250 HP (2% HP increase - probably being generous here). You think someone could feel a "sluggishness" difference if just cruising around at 50 HP or less ... that means they would have to be able to sense a 1 HP or less power difference from the driver's seat. I say no way that's really accurately possible.

Agree on the double blind study ... doubt that anybody could really even feel the difference at WOT in the driver's seat between 250 and 255 HP output.

Agree. Density altitude which constantly changes would have a larger impact on the performance of the engine than 20-30W oil.

 

[ARCOgraphite]

Agree. Density altitude which constantly changes would have a larger impact on the performance of the engine than 20-30W oil.

It is beneficial to hold all variables - except one - constant in this analysis.

As an N.A. engine torque capability is related to P and ρ we can all agree on your point as it is well establish by Boyle and classic physics, chemistry and fluid dynamics.

-Ken

 

[ZeeOSix]

You just jogged my memory that this surprisingly happened to me - and was first noticed - on a 2001 Bullitt with a manual trans. Many Ford service centers didn't have the 5w20 oil for some reason. I brought it to a local L-M dealer for an oil change. they gave me the car back, check the level and filter, all seem well then I headed off. Promptly I said whoa ! Whats wrong?! I look down at the E brake - that was off. Looked out back for and Airstream trailer - that wasn't there.
There was a quite noticeable dulling of the engine response in normal driving. But a fresh tight engine and new unsheared oil.

They put 5W-20 in it because the dealer didn't have it? Of course the engine might have felt a bit off and "sluggish" if the oil and engine wasn't fully warmed up. When all factors are equal and constant, nobody is going to be able to detect the shear friction HP loss due to a 0.5 cP difference in HTHS viscosity in the journal bearings from the driver's seat cruising around. Might not even see it on a dyno at full power output, as the power difference would probably be in the +/- % repeatability if the dyno.

 

[ARCOgraphite]

They put 5W-20 in it because the dealer didn't have it? Of course the engine might have felt a bit off and "sluggish" if the oil and engine wasn't fully warmed up. When all factors are equal and constant, nobody is going to be able to detect the shear friction HP loss due to a 0.5 cP difference in HTHS viscosity in the journal bearings from the driver's seat cruising around. Might not even see it on a dyno at full power output, as the power difference would probably be in the +/- % repeatability if the dyno.

The dealer installed 5w30. This was back when Ford just started the 5w20 recommendation,

Sound implausible on its face for sure and in fact I would welcome the 5W30.

Like I said before, many engines over many years in many cars.

There is a big difference between bench racing and field experience.

 

[Revving2Redline]

Kendall Nitro 60, anyone?

40w70!



https://www.supercheapauto.com.au/p/penrite-penrite-hpr-50-engine-oil---40w-70-5-litre/1098.html

 

[Revving2Redline]

I have a hunch if the EPA and CAFE did not exist they would have a different opinion. Manufactures are telling us removing the spare tire from their vehicles reduce their carbon footprint. No spare = carbon credit. This is not a decision which benefits the owner but puts the owner/operator in a precarious position if they have a blowout in the middle of nowhere. I have to believe the same ideology applies to their decision to recommend 0W-20 in a 3.0 TT.

I'd go 0W-30 without a thought.

It's funny you talk about the no spare tire and carbon credit because my Hyundai Accent 2012 didn't have a tire only a kit that was supposed to slime/fix the tire. My dad went on a hot verbal tangent with the Service Mgr. Told them it looked more like a male performance enhancement tool and proceeded to explain where he could stick it.

Okay, back to the oil..0w20 will work if that's what they say. But, do the also explain to owners that they should maintain it under the severe service schedule? Doubt it.