Transmission cooler question

Davesmopar

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I'm going to be running a large transmission cooler.... 11" X 12" plate and fin type.....

Stand alone or in series with radiator???

Running a 2500 stall....
 

Aspen500

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All depends on how it is to be used. Track only, stand alone. Street use, especially in cold weather, use both aux and radiator coolers. Fluid that's too cold is almost as bad as fluid that's too hot. The ideal temp for auto trans fluid is about 175 degrees.
 

BudW

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Most of the work of the transmission cooler is to warm the ATF - more than it actually cools the ATF. 160-180 degrees F is where automatic transmissions like to run at. It doesn't like to be any cooler and not any hotter.
Most people don't see it but many transmission shift points are off when ATF is cold - but on the same note, it's not good to run the engine hard when it is (also) cold.

For long term street usage, I think one might do more harm with a stand alone air-to-air transmission cooler unless using car for a pulling a trailer or drive a lot in the mountains. In series - it should be OK.
Police cars used transmission coolers after the radiator - but on same note, police cars rarely get turned off.

If a person does plan on driving your car hard or maybe a street/strip car, you might look into what car manufactures use today, which is a transmission cooler line thermostat. The thermostat will re-direct fluid depending on what temperature it is (both too hot or cold).
BudW
 

Davesmopar

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I plan on beating the hell out of it... mainly going to be a red light to red light car with some 1/8 mile track use.....

My cooler lines run between the header and oil pan... I will use some high temp plug boot covers there....


Soo radiator 1st then cooler in series....

Thanks for the advice....
 

Mikes5thAve

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It's also been said cooler first, then rad so that it doesn't over cool. I usually aim for that but mainly go for whatever is easiest line wise.
 

jasperjacko

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Factory police set-up used trans cooler with inline radiator. That's what I have in my car.
 

69-

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My 5t dodge Camper 360/727 has pretty low temps (50-60 Celsius), going up to like 70-80 Celsius in a traffic jam. Stock oil cooler in rad, just a bigger pan (summit) with lowered intake. Thats at like 65 F ambient temp, I will have to see what happens at like 80-90F...
Temp sensor is at the drain plug, so it might be 10 degrees Celsius more inside. I'm fine, even crawling steep hills with less than 40 mph at full throttle.
 

Remow2112

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You mileage may vary but I live in southern AZ and heat here is what killed many a mopar tranny. I run a stacked plate design and take the radiator out of it. But in southern AZ I never really have to worry much about it being too cold and never warming up. I did not know about the temperature stuff BudW. Good info. Strictly anecdotal but I had a 05 Nissan Frontier and they had an issue where the radiator would crack internally and tranny would suck in radiator water. Would eat the tranny. The solution was to bypass the tranny part of the cooler and just use the external. I ran mine that way well over 100k. Once again in AZ. :)

The other thing to consider is a trans go shift kit. The overlap between 1 - 2 and 2 - 3 is also a wear point in the tranny. I always liked the Tran Go 2 kit. But it is a very firm shift.
 

Davesmopar

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I'm running a TF3 full manual.... part throttle at 3K feels like a mule kicking you in the back with 2nd gear, 3rd feels like the car is being hit by a huge sledgehammer..... love it....
 

Duke5A

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I'm using a B&M stacked plate cooler plumbed inline with the cooler built into a Champion radiator. Never goes over 180 degrees with a high stall converter.
 

M_Body_Coupe

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Here is what I have, right in front of the rad, fairly civilized install hanging off of the rad support yoke.

Don't have a temp sensor installed today, but I do run a deep pan on the 727. Car has been through numerous burnouts and pretty good amount of load (4k, 9.5" converter). Can't say I have spotted any issues yet.

I really should toss a temp sensor in, the pan even has a threaded mounting hole for it...just missing a nice spot to install the gauge inside the cabin.

trans_cooler.jpg
 

Oldiron440

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Looks like the oil cooler on a Jaguar I once had.
You can run a transmission too cool.
 

M_Body_Coupe

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Looks like the oil cooler on a Jaguar I once had.
You can run a transmission too cool.
Yeah, that's a great point.

Was actually reading a thread on Moparts the other day on the very same topic: a fellow was considering plumbing a thermostat into the line to make sure the fluid does NOT cool below a certain temp. The general feeling was that about 180F was the goal.

Now this primary use was drag racing, found that the car was a lot more consistent once the temps came up after a few passes.

For street use that may be an overkill, but at least knowing the TEMPs is a good data point to have.
 

BudW

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Most of the newer vehicles (GM and Chrysler do this) have a thermostat built into the transmission cooler lines that will either direct fluid (when cold) to the radiator, back into the transmission when at right temp, or to an external cooler when fluid is hot - which might be the best design. The problem is it requires twice the plumbing - which is equal to twice the potential fluid leaks.

To be consistent for racing, you want the fluid set to a particular temperature that doesn't vary but say 20 degrees - or so. Automatic transmissions do prefer to be at or about 175 to 180 degrees.
That is, by the way, about what the coolant temp is inside of the radiator - so strange on how that works out.
BudW
 

Duke5A

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Here is what I have, right in front of the rad, fairly civilized install hanging off of the rad support yoke.

Don't have a temp sensor installed today, but I do run a deep pan on the 727. Car has been through numerous burnouts and pretty good amount of load (4k, 9.5" converter). Can't say I have spotted any issues yet.

I really should toss a temp sensor in, the pan even has a threaded mounting hole for it...just missing a nice spot to install the gauge inside the cabin.

View attachment 45336
This is the way to do it! I used to have mine mounted to a couple pieces of angle iron running the width of the radiator. I pulled it all out this year after remembering Dariusz's car and mounted it just like this. Should have done this from the beginning. There is more than enough support there to handle it.
 

BudW

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That center bar is designed to support the transmission cooler and engine oil cooler, for police cars.
 

M_Body_Coupe

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That center bar is designed to support the transmission cooler and engine oil cooler, for police cars.
Totally...make no mistake, I take no credit for this genius placement...much sharper minds have produced that, but I will readily admit to taking advantage of as much of that design as possible (such as the lower supporting bracket (see items #10 and #11 on the factory install schematic below).

Here is the 1980 Parts Book diagram, which I modeled my install on.

I had actually acquired all the factory hardware, including the darn two brackets that hold the factory cooler, as well as the clips that capture the transmission lines going over the top of the rad support.

However...given that I went with a different cooler itself, and wanted to take the plumbing and make that as hidden as possible, I ended up doing my own version. If there is anything I am proud of, it is that part...which I unfortunately have no pics of at the moment...LOL!

Cooling line routing - factory.jpg
 
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