Another "Taxi" Study: Relationship of Engine Bearing Wear and Oil Rheology 872128

[Bill7]

That sums it up. Yea, no more thick vs thin threads.
Overkill, ZeeOsix and a few others went to a lot of work and effort posting on this thread.
It's been one of the best in years on bitog.

Right, but that's the point that's been expounded on what has to be 100x already. There's that "magic" HTHS figure, which is somewhere in the neighbourhood of 2.5cP and once you go below that, you are looking at fundamental design changes in order for us to even reach the threshold of "adequate" wear control. He's running an oil with an HTHS below 1.6cP, yeah, it's not surprising we are seeing metal.

So, it's not about "reaching zero" or that 2x a tiny number is still a tiny number. Sure, that might be the case going from 2.6cP in your 5W-20 to 3.0cP in an ILSAC 5W-30, that, overall, there's really no meaningful difference to Average Joe, but that's not what is being discussed and that's certainly not what is going on when you are literally seeing metal chunks in the oil filter.

So, if we are specifically referring to Ali's experiment and not the paper in the OP, then the research from the Honda paper applies, and that is simply that engines require specific design accommodations/alterations in order for wear to be acceptable once you drop below the xW-20 grade; below the ~2.5-2.6cP HTHS realm. His Navigator does not feature an engine configured in this manner. Ergo, any justification that might be applicable to the discussion between say xW-20 and xW-30, xW-40...etc doesn't apply, this is a wholly separate realm that requires mechanical design changes and that bit seems to be getting glossed over.

I think one other thing to consider is xW-20 weight oils in severe service. Adequate wear protection = yes, but optimal = no.
Several new Ford engines are speced for 5W-30 and not 0W-20. If 0W-20 was that good, Ford would spec all it's engines for 0W-20.

This may be because the HTHS = 2.6 is on the borderline of adequate wear protection, but as you get closer to HTHS = 3.5, wear protection becomes optimal.

So within the xW-20, XW-30 comparison, HTHS and MOFT really do matter for high performance engines or severe service.
So why settle for 20 weight adequate protection if you can get optimal protection from 30 weight oils with higher HTHS.
20 weight oils cost the same as 30 weight oils, so it's a no brainer to go with the 30 weight oil.

 

[edhackett]

How can I note the resistance to viscosity drop without knowing the initial viscosity of each formulation?

Ed

Ali has provided me with numbers in a PM. I'm going to keep the discussion private, stepping out of the snake pit. as it were.

Ed

 

[ZeeOSix]

I think one other thing to consider is xW-20 weight oils in severe service. Adequate wear protection = yes, but optimal = no.
Several new Ford engines are speced for 5W-30 and not 0W-20. If 0W-20 was that good, Ford would spec all it's engines for 0W-20.

This may be because the HTHS = 2.6 is on the borderline of adequate wear protection, but as you get closer to HTHS = 3.5, wear protection becomes optimal.

Exactly ... Ford went from the once specified 5W-20 to 5W-30 on the Coyote V8s, and it obviously was not to try and appease CAFE. And it wasn't because the journal bearing clearances changed. It was probably more about cutting down on the warranty claims. And that includes Ford sold extended warranties. Note that Ford did specify 5W-30 for Mustangs with the Coyote in Australia, but at the same time speced 5W-20 for them in the USA.

 

[Bill7]

Exactly ... Ford went from the once specified 5W-20 to 5W-30 on the Coyote V8s, and it obviously was not to try and appease CAFE. And it wasn't because the journal bearing clearances changed. It was probably more about cutting down on the warranty claims. And that includes Ford sold extended warranties. Note that Ford did specify 5W-30 for Mustangs with the Coyote in Australia, but at the same time speced 5W-20 for them in the USA.

So it appears Ford thought 5W-20 wasn't adequate, and they changed the recommendation to 5W-30 for them.

So that's my point, every car can benefit from that extra protection cushion from a 30 weight oil, so you're covered during extreme service that happens unexpectedly like climbing hills / long inclines at slow speeds due to traffic with engine temperature getting hotter than normal. The higher HTHS and MOFT (film thickness) you have, the more engine wear protection you have as parts of the engine reach 150C like the bearings and oil temporarily becomes thinner in those places due to the high heat and high RPM (even though average coolant temperature might be 100C).

If 20 weight and 30 weight oils cost the same, but 30 weight oils have higher HTHS and more film thickness, I don't see the advantage to using a 20 weight oil instead.

 

[ZeeOSix]

so 5W-20 wasn't adequate, so Ford change to 5W-30 for them.

Apparently Ford engineers didn't think it was "adequate" enough - and they lost some CAFE credits by doing it. Lots of Mustang and F150 guy with the Coyote don't run the specified 5W-20 anyway and go with 5W-30 for street use, and xW-40 or xW-50 for track use ... at least the ones that understand it provides better engine protection.

 

[Bill7]

Apparently Ford engineers didn't think it was "adequate" enough - and they lost some CAFE credits by doing it. Lots of Mustang and F150 guy with the Coyote don't run the specified 5W-20 anyway and go with 5W-30 for street use, and xW-40 or xW-50 for track use ... at least the ones that understand it provides better engine protection.

Ford is most likely the best US car maker. Their vehicles actually have average reliability (not like GM or Chrysler that are much worse than average on Consumer Reports). Also, Ford makes some really interesting vehicles, especially their larger SUV's and pickup trucks.
I do trust Ford a lot. My brother bought a new Ford Expedition. It rides nice. It's speced for 5W-30 in the owners manual.

 

[Jetronic]

Yes, yes they did. I believe I brought that up earlier, that 0W-5, not existing in J300, was a serious issue.

I also point to it every time, but no OP ever seems bothered about it

 

[Bill7]

I also point to it every time, but no OP ever seems bothered about it

0W-5, with visible metal debris in oil filter after a 1k oil change on a new engine with only 20k miles on the engine.

I don't know if I could have ever done that experiment with one of my engines.
Every time I would be pressing on the accelerator I'd be thinking about all the wear I just caused.
Engine wear with 1k miles using 0W-5 might be about the same as engine wear after 200k miles with 5W-30.

 

[demarpaint]

Apparently Ford engineers didn't think it was "adequate" enough - and they lost some CAFE credits by doing it. Lots of Mustang and F150 guy with the Coyote don't run the specified 5W-20 anyway and go with 5W-30 for street use, and xW-40 or xW-50 for track use ... at least the ones that understand it provides better engine protection.

They word adequate is catchy, isn't it? It brings out a point, not a good one in this case.

 

[Bill7]

They word adequate is catchy, isn't it? It brings out a point, not a good one in this case.

"adequate" protection is a good way to describe any oils 20 weight or thinner.
"optimal" protection is a good way to describe any oils 30 weight or thicker.

 

[ZeeOSix]

Didn't Neo have a 0W-5 when the lowest grades were xW-20? I recall it wan't much thinner, if any, than a 20.

The Redline "Racing 0W5" being used in the Navigator test has a KV100 of 4.6 cSt and HTHS of 1.58 cP, so if you try to place it in the J300 table it would be slightly above the 4.0 cSt lower limit of SAE 8, but lower HTHS than the 1.7 cP minimum for 8. Since HTHS is more important, and if graded by that it would be below an "8" grade.

5WT Drag Race Oil (0W5)

Popular for class racing in NHRA Stock and Super Stock

www.redlineoil.com

Tested Motor Oil:
Red Line 5WT Racing Oil 0W5 grade
Phosphorus, Avg PPM 3350
Zinc, Avg PPM 2400
Vis @ 100°C, CSt 4.6
Vis @ 40°C, CSt 21.8
Viscosity Index 134
CCS Viscosity, Poise, @ °C 20@-30°C
Pour Point, °C -54
Pour Point, °F -65
NOACK Evaporation Loss,1hr @ 482°F (250°C), % 12
HTHS = 1.58

 

[Bill7]

The Redline "Racing 0W5" being used in the Navigator test has a KV100 of 4.6 cSt and HTHS of 1.58 cP, so if you try to place it in the J300 table it would be slightly above the 4.0 cSt lower limit of SAE 8, but lower HTHS than the 1.7 cP minimum for 8. Since HTHS is more important, and if graded by that it would be below an "8" grade.

5WT Drag Race Oil (0W5)

Popular for class racing in NHRA Stock and Super Stock

www.redlineoil.com

Tested Motor Oil:
Red Line 5WT Racing Oil 0W5 grade
Phosphorus, Avg PPM 3350
Zinc, Avg PPM 2400
Vis @ 100°C, CSt 4.6
Vis @ 40°C, CSt 21.8
Viscosity Index 134
CCS Viscosity, Poise, @ °C 20@-30°C
Pour Point, °C -54
Pour Point, °F -65
NOACK Evaporation Loss,1hr @ 482°F (250°C), % 12
HTHS = 1.58

Phosphorus content is very high. It could be damaging the Navigator's catalytic converter.
I guess it needs the high levels of Phosphorus and Zinc in the additive package to counter the lack of wear protection of the viscosity.

 

[TiGeo]

That sums it up. Yea, no more thick vs thin threads.
Overkill, ZeeOsix and a few others went to a lot of work and effort posting on this thread.
It's been one of the best in years on bitog.

Yes, I understand all of this. I am fully comprehending. Check. I am a bit lost however with what the OP is actually intending to do with his 5W testing or what his overall belief in running thinner oils is - maybe @AEHaas can provide a simple clarification to his belief/intentions here - I *think* he understands what you are saying but is actually going after the concern that I have stated with folks that own vehicles that call for 20W and worry so run 30W or at least in that general realm; I'm not sure he's telling folks to run oils below 20W and that's it's ok but maybe I'm mis-reading his posts. TiGeo probably getting ready to head out before lock/bickering/mods.

 

[TiGeo]

Using examples above from the OEMs about high-powered sports cars (Mustangs w/V8) going from 20 back to 30 as a justification for you to not run 20W in your average-Joe car is not founded and peak-BITOG (see old man carefully driving picture above for more info) in this discussion. Yes, it shows Ford may have found issues doing that with warranty repairs etc. from the guys buying 5.0 Mustang GTs at 30% interest/8 years going out and doing donuts in the street at redline but that is an extreme case; these are ~450hp cars. Also, GR Supra...20W. GR Corolla....0W20. The 20W oils are more than adequate as I see it for average vehicles that are are driven in an average manner..case-in-point my '13 Ford Focus example I've provided. No reason to run thicker oil in that car unless it was tracked and even then, I'd probably not mess with it but certainly could justify it based on the data that has been provided ad nauseam here/elsewhere on BITOG.

Ok screw it. HPL Euro 5W40 in the world!!!!!!!!!

 

[ZeeOSix]

I *think* he understands what you are saying but is actually going after the concern that I have stated with folks that own vehicles that call for 20W and worry so run 30W or at least in that general realm.

There's a big difference between running a 20 in a vehicle that specifies it, and running a 5 in a vehicle that specifies a 30.

And there's absolutely nothing wrong with running a 30 in a vehicle that specifies a 20 for some added HTHS and MOFT headroom - what's wrong or bad about that if someone wants more wear protection for all possible driving conditions?

 

[demarpaint]

There's a big difference between running a 20 in a vehicle that specifies it, and running a 5 in a vehicle that specifies a 30.

And there's absolutely nothing wrong with running a 30 in a vehicle that specifies a 20. HTHS and MOFT headroom - what's wrong or bad about that if someone wants more wear protection for all possible driving conditions?

The problem is some people just don't understand that concept, which is why we have countless threads like this which go on and on and on.

 

[DuckRyder]

When Overkill post it is gonna be a good read.

The visible metal is a problem, but I did not get out of the other thread how many miles are on this Lincoln - is it break in? possible machining swaff (it is not unheard of) or is it wear? If its wear and it is visible metal that is a very bad sign quite obviously.

I'm also not very sure this particular engine is the best choice for the experiment - I believe it is basically a Raptor engine, it is very high specific output, it is specked for a heavier oil and even the "regular" 3.5 EB is known for annihilating oil. But perhaps this is why he chose it for his test. They used to offer it as a crate motor and its probably a $12000.00 engine.

Still it is his and he has been properly warned.

 

[ZeeOSix]

^^^ 29,000 miles, so it's broken in. Info in post #1 in that other thread.

 

[userfriendly]

Yes, I understand all of this. I am fully comprehending. Check. I am a bit lost however with what the OP is actually intending to do with his 5W testing or what his overall belief in running thinner oils is - maybe @AEHaas can provide a simple clarification to his belief/intentions here - I *think* he understands what you are saying but is actually going after the concern that I have stated with folks that own vehicles that call for 20W and worry so run 30W or at least in that general realm; I'm not sure he's telling folks to run oils below 20W and that's it's ok but maybe I'm mis-reading his posts. TiGeo probably getting ready to head out before lock/bickering/mods.

Oh man, if you think this is bickering, you should read the astrophysics forums. They call each other names that would get them a vacation here on their first post. I like to lead-out the experts here by asking questions pretaining to the subject matter. Like; what came first, the thin motor oils or the engine structure changes that allowed the thin oils to be an all season grade.

A man's gotta know his limitations. Writing technical posts is time consuming and hard work. I'm a highschool dropout, rusty, unemployed and out of practice. I'm finally learning the difference between your and you're, there, their and the're and its and it's.

 

[4WD]

The problem is some people just don't understand that concept, which is why we have countless threads like this which go on and on and on.

True - but lots of drone from the same folks who who have to be right …
I just speed read the fringe stuff or a handful of members - 80% is so predictable …