Synthetic and heat transfer

[aquariuscsm]

Originally Posted By: dave1251
Originally Posted By: aquariuscsm
Originally Posted By: JHZR2
Originally Posted By: aquariuscsm
I`d be willing to bet that was back when synths were pao/ester based before the grp III`s came along.


So cite a difference in heat capacity before making claims that are just out there. I know plenty of folks have a hatred for grp III, but spreading fallacies does not do anything for your case.


I`m not citing or making any claims,I made a basic assumption. How would conventional oil be different from conventional oil? I never made a claim of temp differences,I was making an assumption on the op`s claim. A case? Huh???????



You are aware PAO is "conventional" oil also right?


ALL oil comes from good ol Mother Earth. BUT,what I said,well,was more of a question (so therefore I NEVER made a claim) was *quoting myself*,"How is a conventional different from a conventional"? A quote from my original comment,"I`d be willing to bet that was back when synths were pao/ester based*. I "willed to bet",which is an assumption on my part. I have no idea if it does or doesn`t,therefore I started an assumption because,I have no idea. But,just like you and every other lil BOTOG`er,I`d LOVE to know! Ah yes,the eternal human quest for knowledge :^)

 

[dave1251]

Yes I agree, do you agree you would can a greater volume of heat transfer if a less viscous fluid was used? This would be a greater use of the resources you have at hand than making a assumption that a different group of fluids would have an adverse effect of heat transfer coefficient if the grade of the fluids in question are the same. Do you agree?

 

[aquariuscsm]

RP claims lower gearbox temp if you use their PAO gear oil.

RP:
Maximizes horsepower
Extends gear and bearing life
*Reduces operating temperature*
Severe service performance
Lower coefficient of friction
Superior corrosion protection
Separates rapidly from water
Meets warranty requirements
Environmentally responsible
Formulated for limited-slip differential use

 

[Hyde244]

Originally Posted By: JHZR2
Have GC or GC/MS results to validate that claim? There is still going to be a major distirbution of products from a synthesis reaction. The catalysis is NOT that selective.

... Again, data? Its easy to get a molecular weight distribution of a finished product to prove this or disprove this. Given that additives such as Z-max have been effectively disproven on here, when this mechanism was stated as the way they work, what gives syn oils a free pass?
There is plenty of experts to refer to on the advantages of synthetic oil:

Mobil 1: http://www.mobiloil.com/USA-English/MotorOil/Synthetics/What_Is_Synthetic_Motor_Oil.aspx
Motorcraft: https://www.youtube.com/watch?v=-4B6Aw3Ej4o
Valvoline: http://www.valvoline.com/faqs/motor-oil/full-synthetic-motor-oil/
Wikipedia: https://en.wikipedia.org/wiki/Synthetic_oil#Automotive_use
Popular Mechanics: http://www.popularmechanics.com/cars/how-to/products/4232672

Do I have actually data sheets, etc.? Of course not - I trust that an entire industry is probably going to get the facts right on what oil is recommended when. You can question the process used for creating synthetic oil and the advantages of its use.

I will side with the mechanics and engineers who say that it has a proper application, as they have invested plenty of money into research and development for this exact question. There is a reason why Ford does not have a conventional Motorcraft oil - synthetic has it's upsides.

Synthetic's biggest advantages are: 1. heavy engine operation, such as towing 2. cold start-ups 3. prolonged OCI.

If you don't do any of those - dino is fine. If you do, synthetic or a synthetic blend might be something to consider.

 

[dave1251]

Originally Posted By: aquariuscsm
RP claims lower gearbox temp is you use their PAO gear oil.

RP:
Maximizes horsepower
Extends gear and bearing life
*Reduces operating temperature*
Severe service performance
Lower coefficient of friction
Superior corrosion protection
Separates rapidly from water
Meets warranty requirements
Environmentally responsible
Formulated for limited-slip differential use



And members say that when RP makes ridiculous marketing statements I am a hater. Yes it reduces operating temperature compared to a differential with no fluid.

 

[aquariuscsm]

Originally Posted By: dave1251
Originally Posted By: aquariuscsm
RP claims lower gearbox temp is you use their PAO gear oil.

RP:
Maximizes horsepower
Extends gear and bearing life
*Reduces operating temperature*
Severe service performance
Lower coefficient of friction
Superior corrosion protection
Separates rapidly from water
Meets warranty requirements
Environmentally responsible
Formulated for limited-slip differential use



And members say that when RP makes ridiculous marketing statements I am a hater. Yes it reduces operating temperature compared to a differential with no fluid.


I don`t buy the lower temp thing either. I`m not an RP hater (I love their Synerlec oil) but Max Gear was HORRIBLE in my manual transmission. But hey,they`re in it to make money just like everyone else. Without money,we don`t eat,unfortunately.

I tried it in my car`s rear diff too and had subpar results.

 

[mechtech2]

Originally Posted By: dparm
Originally Posted By: Boatowner
I know synthetics are generally considered to be slicker than conventional oil, which means engines should run a little cooler. Also, a synthetic is going to stand up to the high heat of hard running better. Whether any of that means synthetics transfer heat better I have no idea. However, in order to transfer heat the oil had to send it somewhere else, so I kind of doubt it.



Slicker? What do you mean?


Slicker Ad campaigns convinvced him that Full Synthetic oil is slicker.

 

[electrolover]

Originally Posted By: Stelth
Some years ago, I read an article in some sort of RV publication about synthetic oils. The article said that synthetic oils are better heat transfer fluids than conventional oils. It also said that since the pistons are basically oil-cooled, a synthetic would be better under severe conditions, such as a loaded-down motorhome climbing a hill.

Any truth to this?


I think so. I was watching nascar garage a while back and one of the crew chiefs said they use syn because its better at carrying away heat, particularly from the valvesprings, which is a big concern of theirs

 

[aquariuscsm]

Originally Posted By: mechtech2
Slicker Ad campaigns convinvced him that Full Synthetic oil is slicker.


Haha good one ;^)

 

[dave1251]

Originally Posted By: Hyde244
Originally Posted By: JHZR2
Have GC or GC/MS results to validate that claim? There is still going to be a major distirbution of products from a synthesis reaction. The catalysis is NOT that selective.

... Again, data? Its easy to get a molecular weight distribution of a finished product to prove this or disprove this. Given that additives such as Z-max have been effectively disproven on here, when this mechanism was stated as the way they work, what gives syn oils a free pass?
There is plenty of experts to refer to on the advantages of synthetic oil:

Mobil 1: http://www.mobiloil.com/USA-English/MotorOil/Synthetics/What_Is_Synthetic_Motor_Oil.aspx
Motorcraft: https://www.youtube.com/watch?v=-4B6Aw3Ej4o
Valvoline: http://www.valvoline.com/faqs/motor-oil/full-synthetic-motor-oil/
Wikipedia: https://en.wikipedia.org/wiki/Synthetic_oil#Automotive_use
Popular Mechanics: http://www.popularmechanics.com/cars/how-to/products/4232672

Do I have actually data sheets, etc.? Of course not - I trust that an entire industry is probably going to get the facts right on what oil is recommended when. You can question the process used for creating synthetic oil and the advantages of its use.

I will side with the mechanics and engineers who say that it has a proper application, as they have invested plenty of money into research and development for this exact question. There is a reason why Ford does not have a conventional Motorcraft oil - synthetic has it's upsides.

Synthetic's biggest advantages are: 1. heavy engine operation, such as towing 2. cold start-ups 3. prolonged OCI.

If you don't do any of those - dino is fine. If you do, synthetic or a synthetic blend might be something to consider.


When you state that there is a reason why Motorcraft is not a conventional you are talking out loud on a subject you do not have complete knowledge of.

Do you know why Motorcraft and other Phillips oils are blends? It has little to do with what you believe to be true. It is a more cost effective process for Phillips PCMO's to meet and pass ISLAC and API specs than the route other blenders used to obtain the specs.

 

[aquariuscsm]

Heck,Pennzoil Conventional feels more slippery than Mobil 1 *shrug*

 

[electrolover]

I can tell you two things about RP gear oil.

1) I have been running it in my truck with no problems

2) the dirt trackers here swear by it because if they have to do a gear change at the track they dont get burnt, like when they run dino. They say the difference is night and day compared to dino after a race.

 

[MolaKule]

Quote:
Some years ago, I read an article in some sort of RV publication about synthetic oils. The article said that synthetic oils are better heat transfer fluids than conventional oils. It also said that since the pistons are basically oil-cooled, a synthetic would be better under severe conditions, such as a loaded-down motorhome climbing a hill.

Any truth to this?




This topic has come up at least six times and somewhere in the bowls of BITOG I once did a calculation on mineral verses synthetic oil heat transfer and synthsized oils have a very small advantage in terms of heat transfer.

If you can reduce friction in the moving parts interfaces, you can reduce heat at those points, which is where syntheszed oils have a sight advantage over mineral oils.

See Table 5 from this link:

http://books.google.com/books?id=J_AkNu-...nts&f=false

you can use this formula:

CP at T = 4.19*((0.402+0.00081*T)/D^0.5)

CP at T: Specific Heat @ constant P (kJ/kg.K)
T : Temperature ( C )
D : Density at 15 C (g/cm3)

Find the density @ T, and then calculate with ASTM D 1298 to find Density @ 15 C

 

[JHZR2]

Originally Posted By: Hyde244

Synthetic's biggest advantages are: 1. heavy engine operation, such as towing 2. cold start-ups 3. prolonged OCI.

If you don't do any of those - dino is fine. If you do, synthetic or a synthetic blend might be something to consider.


No kidding. I advocate syn for most uses and have syn in all my vehicles and OPE.

But it doesn't mean that I buy that there is a meaningfully substantial difference in practice. As I stated earlier, the thermal conductivity difference is in the second decimal place.

Changing to an entirely different viscosity that flows a lot more could well move more fluid which given a more consistent delta t could possibly cool a bit more. But that's a major viscosity difference, not the variants in some nominal flow difference due to alignment of molecules in some syn oil.

 

[JHZR2]

Originally Posted By: MolaKule
Quote:
Some years ago, I read an article in some sort of RV publication about synthetic oils. The article said that synthetic oils are better heat transfer fluids than conventional oils. It also said that since the pistons are basically oil-cooled, a synthetic would be better under severe conditions, such as a loaded-down motorhome climbing a hill.

Any truth to this?




This topic has come up at least six times and somewhere in the bowls of BITOG I once did a calculation on mineral verses synthetic oil heat transfer and synthsized oils have a very small advantage in terms of heat transfer.

If you can reduce friction in the moving parts interfaces, you can reduce heat at those points, which is where syntheszed oils have a sight advantage over mineral oils.

See Table 5 from this link:

http://books.google.com/books?id=J_AkNu-...nts&f=false

you can use this formula:

CP at T = 4.19*((0.402+0.00081*T)/D^0.5)

CP at T: Specific Heat @ constant P (kJ/kg.K)
T : Temperature ( C )
D : Density at 15 C (g/cm3)

Find the density @ T, and then calculate with ASTM D 1298 to find Density @ 15 C



What's the difference in viscosity of, say, a 10 cst pao vs other 10cst basestocks?

 

[JAG]

Originally Posted By: MolaKule
See Table 5 from this link:

http://books.google.com/books?id=J_AkNu-...nts&f=false


That particular ester in Table 5 had 11.8% higher lube heat transfer coefficient than the PAO did, and 35% more than the mineral oil. Those are significant differences. One caveat: I think that mineral oil is napthenic which is not found in significant percentages in typical currently-sold motor oils, so we shouldn't associate it with current non-synthetic-based motor oils.

 

[DBMaster]

Originally Posted By: JHZR2
Totally uninformed amsoil rep. Do you even know what laminar and turbulent flow is?


Hopefully, I didn't sound like I was speaking as an authority. I avoid doing that if I am not sure I know what I'm talking about. I was quoting that Amsoil guy, who was a fairly high level upline in Texas. The anecdote of Mobil 1 causing the Thunderbird to remain in a normal temperature range was directly observed by me. But, that was Mobil 1 from 1990. I have no idea if it would be true today of Mobil 1 in all its various formulations, or if it would be true of other synthetics. Today's conventional oils might even have the same effect.

I had better watch out. I'm going to be even more careful now with my semantics and not make statements in a thread for which I am not an absolute expert, like the rest of you apparently are.

 

[Clevy]

I read all the time in the Harley forums I'm in about how synthetic lowered their engine temps.
I've never seen it. In fact when I first used a syn in my Harley the oil temp was higher. I had a dipstick temp gauge. Not that I put much faith in it.

 

[tig1]

Heat transfer is the wrong word. Synthetic oils are more capable of handling higher temps than dino. Like others said, do to their ability to resist oxidation, ring coking and varnish is greatly reduced.

 

[JHZR2]

Originally Posted By: tig1
Heat transfer is the wrong word. Synthetic oils are more capable of handling higher temps than dino. Like others said, do to their ability to resist oxidation, ring coking and varnish is greatly reduced.


That is sensible.