Thin or thick (TGMO 0W-20/M1 0W-40): Final verdict

[Gokhan]

Originally Posted by edyvw
I actually live there part time, so I am aware of that. I am now afraid my car might blow up because, you know, I-15.

No worries, just get a Toyota if it blows up. A Toyota will never leave you stranded.

 

[edyvw]

Originally Posted by Gokhan
Originally Posted by edyvw
I actually live there part time, so I am aware of that. I am now afraid my car might blow up because, you know, I-15.

No worries, just get a Toyota if it blows up. A Toyota will never leave you stranded.

Yeah, right.
But I am afraid I will boil up inside considering it is thick as cheap beer can.

 

[PimTac]

I've driven over the Siskyous complex several times. It's a common sight to see many cars and trucks along the way pulled over with hoods up. The Siskyous is not a high pass like in Colorado but it's a series of passes that starts way back around Roseburg Oregon and ends in Redding Ca is headed south.

Any decent pass can be a workout for a engine and vehicle. Altitude is just one factor.

 

[ZeeOSix]

Dry air has more thermal conductivity than humid air.

The Thermal Conductivity of Moist Air
https://www.electronics-cooling.com/2003/11/the-thermal-conductivity-of-moist-air/

 

[Gokhan]

Originally Posted by PimTac
I've driven over the Siskyous complex several times. It's a common sight to see many cars and trucks along the way pulled over with hoods up. The Siskyous is not a high pass like in Colorado but it's a series of passes that starts way back around Roseburg Oregon and ends in Redding Ca is headed south.

Any decent pass can be a workout for a engine and vehicle. Altitude is just one factor.

Exactly, it's a workout for most cars. There are many factors, the ambient temperature being a crucial one.

Nevertheless, edyvw drove up the grade (or perhaps down the grade

) at almost twice the speed limit (70 MPH) without a sweat and getting caught. He must have the 300 hp version of the VW CC. To each his own.

Originally Posted by edyvw
Originally Posted by Gokhan
http://wikimapia.org/24673889/Baker-Grade
I have drove that part numerous times. I actually hit 130mph going that grade with VW CC (well, that was limiter). It is absolutely unremarkable difficulty.

 

[Gokhan]

Originally Posted by ZeeOSix
Dry air has more thermal conductivity than humid air. The thermal conductivity of air also decreases with increased temperature.

The Thermal Conductivity of Moist Air
https://www.electronics-cooling.com/2003/11/the-thermal-conductivity-of-moist-air/

True, I know this reference. However, the heat capacity plays a bigger role than the thermal conductivity of the air. This paper claims that you can remove up to 35% more power with humid air, although the relative humidity is near 100%. Your results will vary if the humidity is not that high:

https://www.researchgate.net/public...idity_on_effectiveness_of_heat_sink_work

"Higher power may be dissipated in the transistor junction (about 35% according to the measurements) without increasing its temperature and size of the heat sink."

I feel like the thread has been hijacked. Can we go back to discussing the oil?

 

[ZeeOSix]

Originally Posted by Gokhan
True, I know this reference. However, the heat capacity plays a bigger role than the thermal conductivity of the air. This paper claims that you can remove up to 35% more power with humid air, although the relative humidity is near 100%. Your results will vary if the humidity is not that high:


Yep, heat capacity too ... but with air rushing past a hot radiator the thermal conductivity is probably the main heat transere factor over heat capacity (fresh new air constantly coming in). Go back and look at the post I made ... added the graph and shows the curves are not linear if the humidity is above 0%.

 

[Gokhan]

Originally Posted by ZeeOSix
Go back and look at the post I made ... added the graph which shows what you describe. The curves are not linear if the humidity is above 0%.

Yes, I know that graph. We're talking about air convection here. Therefore, you need to take into account both the thermal resistance and heat capacitance of the air. The paper I linked is more informative on what happens to the cooling when the humidity is involved.

 

[Gokhan]

Originally Posted by ZeeOSix
Yep, heat capacity too ... but with air rushing past a hot radiator the thermal conductivity is probably the main heat transere factor over heat capacity (fresh new air constantly coming in).

OK, you edited your post.

Without an actual calculation, we're only speculating here. In any case, there will be some effect of the humidity.

 

[ZeeOSix]

Originally Posted by Gokhan
Originally Posted by ZeeOSix
Go back and look at the post I made ... added the graph which shows what you describe. The curves are not linear if the humidity is above 0%.

Yes, I know that graph. We're talking about air convection here. Therefore, you need to take into account both the thermal resistance and heat capacitance of the air. The paper I linked is more informative on what happens to the cooling when the humidity is involved.


That paper you linked is talking about natural convection ... no mention of air blowing over the heat sink/radiator. The radiator in a car while moving is forced convection. Two different animals.

 

[PimTac]

In the end the oil held up well. That is the main point of this discussion.

 

[Gokhan]

Originally Posted by ZeeOSix
That paper you linked is talking about natural convection ... no mention of air blowing over the heat sink/radiator. The radiator in a car while moving is forced convection. Two different animals.

Fine, here is a very good paper that studied forced-air cooling and did an actual, complex calculation, with the Reynolds number (Re) ranging into turbulent flow:

http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-56092015000300006

"The heat-transfer rate increased about 20% when using air with 90% relative humidity passing through a rectangular microchannel heat sink made of copper."

So, even with forced-air cooling, the humidity is your friend, not your enemy.

 

[Gokhan]

Originally Posted by PimTac
In the end the oil held up well. That is the main point of this discussion.

Yeah, I'm inclined to try the M1 EP 0W-20, which should be much more stout than the TGMO in terms of the initial TBN, TBN retention (Mg), and oxidation resistance (PAO). Plus, it's a little thicker (HTHSV = 2.7 cP) and I still get to enjoy all the benefits of a thin oil plus a very top-quality synthetic. I think my slightly elevated chromium and copper numbers are because of the TBN/oxidation issues, not the viscosity.

 

[ZeeOSix]

Originally Posted by Gokhan
Originally Posted by ZeeOSix
That paper you linked is talking about natural convection ... no mention of air blowing over the heat sink/radiator. The radiator in a car while moving is forced convection. Two different animals.

Fine, here is a very good paper that studied forced-air cooling and did an actual, complex calculation, with the Reynolds number (Re) ranging into turbulent flow:

http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-56092015000300006

"The heat-transfer rate increased about 20% when using air with 90% relative humidity passing through a rectangular microchannel heat sink made of copper."

So, even with forced-air cooling, the humidity is your friend, not your enemy.


But did they verify their modeling accuracy with actual empirical test methods? Mathematical models can be somewhat worthless without verification through accurate valid test methods.

I'm sure it's a complex relationship between air temperature, density and humidity. At any rate, I agree that humidity does have an effect on convective heat transfer.

 

[OilUzer]

Originally Posted by Gokhan
Back to thin or thick.

I got the results for the OCI with TGMO 0W-20 SN after the OCI with M1 0W-40 SN. They are similar. The verdict could be that the oil viscosity doesn't matter that much. I may try a 15W-40 HDEO this time to see what happens. This will be a very long trial.

UOA (link): TGMO 0W-20 SN (Toyota), TBN/TAN, 5142 M, 85 Corolla 4A-LC

1985 Toyota Corolla LE, 4A-LC engine
Mobil 1 Extended Performance M1-103 oil filter
5142 miles and 622 days on oil (yes, almost two years)
Mostly short trips (probably hard on oil)
Sampled through the dipstick using the Blackstone vacuum pump
Oil level was about 0.3 quart low, slightly more consumption than the previous 0.2 quarts
No makeup oil used
UOA by Wear Check
Oil used was TGMO 0W-20 SN ©2015. It turned out that it had no high moly and probably no GTL either!

The results are similar to those in the past, including for M1 0W-40, except for copper, which came almost twice as much this time. Lead was low. Aluminum was low. Chromium is still a tad bit high. Iron is normal. TAN and TBN are both good.

It's hard to say whether thick or thin is better. However, M1 had the best results on chromium. Perhaps I'll try a thick 15W-40 this time to see what it does.

I'm not sure if the premium, high-efficiency oil filter helped but lead was good.

I also don't know where the extra copper came from but perhaps there was some bearing wear.

It looks like the coolant seep has stopped.

I thought tgmo was a very high moly oil. Is this the new version of tgmo with tri-nuclear moly?
PYB has twice the moly!

 

[Gokhan]

Originally Posted by OilUzer
I thought tgmo was a very high moly oil. Is this the new version of tgmo with tri-nuclear moly?
PYB has twice the moly!

Formulation of TGMO is quite inconsistent. Yes, this is the same old version with trinuclear moly and Group III base oil. There was some GTL high-moly version at one point but I wasn't lucky to get that one. The current version may not even be ultra-high-VI as far as I know.

PYB is very old. It had the worst wear despite the mid-moly, perhaps because it was conventional.

 

[OilUzer]

Originally Posted by Gokhan
Originally Posted by OilUzer
I thought tgmo was a very high moly oil. Is this the new version of tgmo with tri-nuclear moly?
PYB has twice the moly!

Formulation of TGMO is quite inconsistent. Yes, this is the same old version with trinuclear moly and Group III base oil. There was some GTL high-moly version at one point but I wasn't lucky to get that one. The current version may not even be ultra-high-VI as far as I know.

PYB is very old. It had the worst wear despite the mid-moly, perhaps because it was conventional.


Can the tests (e.g. Blackstone uoa) distinguish between different molys! Like if one oil has 800 old fashioned moly and another oil has 200 of more effective? moly (trinuclear?), would the voa show 800 and 200 under the moly count?

 

[Gokhan]

Originally Posted by OilUzer
Can the tests (e.g. Blackstone uoa) distinguish between different molys! Like if one oil has 800 old fashioned moly and another oil has 200 of more effective? moly (trinuclear?), would the voa show 800 and 200 under the moly count?

The ppm number simply shows the amount of elemental molybdenum in the oil. It doesn't show the molecular structure, for example trinuclear meaning three molybdenum atoms per molecule.

However, it's possible to determine the type of the moly, base stocks, etc. through FTIR (Fourier-transform infrared spectroscopy) by comparing the spectral lines to known samples.

 

[Shannow]

Originally Posted by ZeeOSix
Originally Posted by Gokhan
Originally Posted by ZeeOSix
That paper you linked is talking about natural convection ... no mention of air blowing over the heat sink/radiator. The radiator in a car while moving is forced convection. Two different animals.

Fine, here is a very good paper that studied forced-air cooling and did an actual, complex calculation, with the Reynolds number (Re) ranging into turbulent flow:

http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-56092015000300006

"The heat-transfer rate increased about 20% when using air with 90% relative humidity passing through a rectangular microchannel heat sink made of copper."

So, even with forced-air cooling, the humidity is your friend, not your enemy.


But did they verify their modeling accuracy with actual empirical test methods? Mathematical models can be somewhat worthless without verification through accurate valid test methods.

I'm sure it's a complex relationship between air temperature, density and humidity. At any rate, I agree that humidity does have an effect on convective heat transfer.


Sorry, I'm late for this hijacking, and send my sincerest apologies for not being earlier in the fray.

Transformer experience is that humidity in either a forced or natural convection radiator reduces effectiveness
http://www.cired.net/publications/cired2011/part1/papers/CIRED2011_0666_final.pdf

But the differences in an IC engine ???

Peak combustion temperatures are down, as is WOT power output...so I'd call it a wash.

 

[Shannow]

Originally Posted by Gokhan
Originally Posted by OilUzer
I thought tgmo was a very high moly oil. Is this the new version of tgmo with tri-nuclear moly?
PYB has twice the moly!

Formulation of TGMO is quite inconsistent. Yes, this is the same old version with trinuclear moly and Group III base oil. There was some GTL high-moly version at one point but I wasn't lucky to get that one. The current version may not even be ultra-high-VI as far as I know.


There's a full half dozen TGMO formulations, varying moly both traditional and (apparently) trinuclear...shear stable, and 10% HTHS loss in 400 miles.

But interestingly, the were all designed specifically for every single Toyota engine, which in turn was designed specifically around those (six) unique oil blends.