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Yes it does require more energy,the biggest factor though will be power(the rate at which the energy is transferred) you could obviously still heat both to 180f they would just reach that temp at different times and under different driving conditions.You calculate the time it takes to heat a object using Q=mcT
Q=energy required
m=mass(kg)
c=specific heat capacity(Joules)
T=(End Temp - Start Temp)temperature difference(K)

20qts example
m=18.9kg
c=2000joules
T=180F - 80F=310.9K
Q=18.9*2000*310.9
Q=‭11,752,020‬ Joules
using 74.569kw
time=157 seconds / 60 = 2.6 minutes
using 25hp = 18.625kw
time=630 seconds / 60 = 10.5 minutes

16qts
m=15.1kg
c=2000joules
T=180F-80F=310.9K
Q=15.1*2000*310.9
Q=9,389,180‬ Joules
using 74.569kw
time=125 seconds / 60 = 2 minutes
using 25hp = 18.625kw
time=504 seconds / 60 = 8.4 minutes

Now to find the time it will take to reach Q we need to know Power which would be the engine output at that moment.
Say are TC is unlocked making 100hp convert to watts 74,569w time=Q/p it would take 157seconds or 2.6minutes,now we arent taking into account heat loss,or the fact that power changes occur this is assuming all the energy is transferred via the ATF only and is a constant 100hp.Ideally a scenario were your TC is unlocked and your at low vehicle speeds would be city driving or stuck in traffic that would constantly have your power changing from stopping and going.Were as cruising on the highway your in a steady state plenty of wind flow,not that much power being used,and your TC is locked.

You also have to remember that the tradeoff you get with a deeper pan is it takes a longer amount of time to heat the fluid which in certain cases is good,but it will take more time to cool the 20qts then it would 16qts if the 20qts would be in a overheat condition.I personally would rather have the fast temperature changes,then add a extra cooler if my temps were getting to high.
 

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So you're saying it takes the same amount of heat energy to maintain 16 qts of fluid at 180 degree as it does to maintain 20 qts of fluid at the same temp? I'm not talking about how long it takes to reach 180 degrees. Obviously that will take a different amount of time. I'm talking about how much heat energy it takes to MAINTAIN each quantity at 180 degrees. I submit that it does take more energy to keep 20 qts of fluid at 180 than it does 16 qts, in which case, it is shedding the heat somewhere.

But the truth remains that if your goal is to cool your transmission fluid, add more cooling, not necessarily more quantity. But, given the choice, I will ALWAYS run more fluid. The 5R110's I build hold an additional 6 qts of fluid, and the 6R140's hold an additional 8 quarts.
 

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I agree it requires more energy to reach 180f of 20qts vs 16qts as it shows in the examples when you solve for Q.I was just showing the tradeoff you get off between the two fluid capacities, the transfer rate of energy is what i would consider more important then max heat capacity of the fluid.
 

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I still don't buy any of it. The added cooling of the fins or the extra capacity making any real-world difference.

I acknowledge the stiffer aluminum pan would add some level of reinforcement to the case, makes sense, I guess that could matter if you're putting a ton of HP through it, but I doubt anyone has actual evidence of that helping. I also acknowledge that it would take a little longer to warm up the fluid, but ultimately I fail to see how that would help maintain better cooling of a trans that's not doing well. If the trans is perfectly healthy it should not be overheating even with the stock pan so... the pan is a band-aid there?

So I guess if you want a fancy drain plug, temp sensor port, and to spend more on fluid, go for it! but I'm calling BS otherwise. Sorry, y'all. I do understand if you're getting a $6000 built trans from a fancy shop, what's a few hundred more for a fancy pan? sure, why not right? Personally I would still ask for a normal capacity fancy pan.
 

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I acknowledge the stiffer aluminum pan would add some level of reinforcement to the case, makes sense, I guess that could matter if you're putting a ton of HP through it, but I doubt anyone has actual evidence of that helping
It's the main reason why I use aluminum pans on every build package, like I've said multiple times. And yes, I have evidence of it not only helping, but actually solving issues...much evidence. It's a cheap and easy way to fix one of the glaring design weaknesses of the 47/48 transmission. There is literally no structure in the bottom of the case...none. Many of the applications that I build for are putting a tremendous amount of power through them. I would not dream of running a stock pan (or any stamped steel pan) on any of those builds.

If you're trying to add cooling, a pan would not be the first way that I would suggest going about it. You need to upgrade the cooling system if you want more cooling. But, running an extra gallon of fluid does add to the cooling capacity of your system. It takes more heat energy to keep 20 qts of ATF at 180 degrees than it does to keep 16 qts of ATF at 180 degrees, so it's shedding heat somewhere. It's the laws of physics at work. You can call BS on it as much as you'd like, but I'll take my 30 years of experience and facts that I've observed and quantified any day.

But, the great news is that you're perfectly free to run absolutely any pan you'd like.
 

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Well, I love my fancy built trans with my fancy deep pan and fancy drain plug that was installed at a fancy shop.


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Yes it does require more energy,the biggest factor though will be power(the rate at which the energy is transferred) you could obviously still heat both to 180f they would just reach that temp at different times and under different driving conditions.You calculate the time it takes to heat a object using Q=mcT
Q=energy required
m=mass(kg)
c=specific heat capacity(Joules)
T=(End Temp - Start Temp)temperature difference(K)

20qts example
m=18.9kg
c=2000joules
T=180F - 80F=310.9K
Q=18.9*2000*310.9
Q=‭11,752,020‬ Joules
using 74.569kw
time=157 seconds / 60 = 2.6 minutes
using 25hp = 18.625kw
time=630 seconds / 60 = 10.5 minutes

16qts
m=15.1kg
c=2000joules
T=180F-80F=310.9K
Q=15.1*2000*310.9
Q=9,389,180‬ Joules
using 74.569kw
time=125 seconds / 60 = 2 minutes
using 25hp = 18.625kw
time=504 seconds / 60 = 8.4 minutes

Now to find the time it will take to reach Q we need to know Power which would be the engine output at that moment.
Say are TC is unlocked making 100hp convert to watts 74,569w time=Q/p it would take 157seconds or 2.6minutes,now we arent taking into account heat loss,or the fact that power changes occur this is assuming all the energy is transferred via the ATF only and is a constant 100hp.Ideally a scenario were your TC is unlocked and your at low vehicle speeds would be city driving or stuck in traffic that would constantly have your power changing from stopping and going.Were as cruising on the highway your in a steady state plenty of wind flow,not that much power being used,and your TC is locked.

You also have to remember that the tradeoff you get with a deeper pan is it takes a longer amount of time to heat the fluid which in certain cases is good,but it will take more time to cool the 20qts then it would 16qts if the 20qts would be in a overheat condition.I personally would rather have the fast temperature changes,then add a extra cooler if my temps were getting to high.
Ok so I want to expand on this, because what I have found is actually very interesting. I would like to point out, that it is VERY possible I did the math wrong haha.

But, while the above was absolutely correct, Arny, it is only one piece of this equation. What we really need is an equation for "operating heat" not "start up heat" which was calculated above, although they are similar.

I apologize in advance, this equation uses Watts as the energy unit, but the equation proves an interesting point all the same.

Watt=
Weight of Material to be Heated (lbs) X Specific Heat (Btu/lb °F) X Temperature Rise (°F)
----------------------------------------------------------------------------------
3.412 Btu/watt hr. X Heat - up time (hr.)

So! using .45 as the specific heat for an oil, 100 degrees of temperature rise (80 to 180), and a heat up time using the values Arny got we get!

20qts: 4860 watts
16qts: 4853.57 watts

So as it turns out, the difference in the extra 4 qts is VERY negligible. I am actually incredible surprised by this, as I thought it would be way more. However, over a long period of time, those 7 watts of extra energy may actually make a huge difference, its hard to say.

Again I feel the need to point out that this equation is for Watts instead of Joules for energy, but it makes the point all the same. Other factors are important too, like the surface area of the deeper pan that allows more air flow etc. But its interesting to see the numbers. All in all, the deep pan helps, but not as much as we would probably like to think. I think its stronger pros are for more strength in the case, it looks sweet, easy to drain magnetic plug, and the sensor port.

Let me know anyone can see a flaw in the math!
 
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I think your math is probably right on. And your conclusion has been my point all along - it's a negligible difference, but it is a difference. If I'm looking for more cooling, I'm not looking to the pan for help. But, if I'm putting a heavy aluminum pan on anyway for other reasons, I'm adding the the extra gallon of fluid to the system. The fluid reservoir becomes a larger thermal mass, which helps absorb and smooth out temperature spikes, creating a more consistent operating temperature, and it does add a small amount of cooling. There really is no downside.
 

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I think your math is probably right on. And your conclusion has been my point all along - it's a negligible difference, but it is a difference. If I'm looking for more cooling, I'm not looking to the pan for help. But, if I'm putting a heavy aluminum pan on anyway for other reasons, I'm adding the the extra gallon of fluid to the system. The fluid reservoir becomes a larger thermal mass, which helps absorb and smooth out temperature spikes, creating a more consistent operating temperature, and it does add a small amount of cooling. There really is no downside.
Agreed, I honestly don't really see a downside other than the money spent.
 

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Damn, Bigman, you got some math skills. Impressed, hahaha. I keep it simple. I listen to those that just KNOW.


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Damn, Bigman, you got some math skills. Impressed, hahaha. I keep it simple. I listen to those that just KNOW.


Sent from my iPhone using Tapatalk
haha thanks man! I just wanted to try and prove something through tangible means instead of everyone just guessing. I was also VERY bored with the quarantine haha
 

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ha ha! some really points on both sides. these threads are great. for me its all about having a drain plug that does not leak......
 
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Lots of better choices than Mag Hytec trans pans
 

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I've experienced it both ways. My current 5.9L didn't make much of a temp difference. It takes longer to heat up but it still gets to the same temp eventually.
 
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