Transmission Cooler Question

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Calipag

Calipag

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The 904 transmission gave up on us and is at the shop being rebuilt. The shop recommended a trans cooler be installed. In the past I've always installed trans coolers (maybe wrong) and eliminated the fluid from running through the radiator. I'm now older and with the good old google machine, see that running it in conjunction with the radiator cooler is the proper (?) way of installing a trans cooler?

My question is when installing this cooler should it be installed in line with the radiator?

The car is a 70 Dart( daily driver), 318 stock rebuild with a edelbrock intake and 4 barrel carb, with a 27 in radiator (aftermarket non aluminum) with a clutch fan. We do live in SoCal and we've already seen 105 degree days here this year and with traffic, things do get warm.

Here is the link to the cooler we are installing:
https://www.amazon.com/gp/product/B000C3BBEY/?tag=joeychgo-20

IMG_5393.JPG
 
Rad first then to the bottom of the cooler and out the top. Always feed the cooler from the bottom to push the air out of the the top.
 
nowadays, you have much better choices in auxiliary trans coolers. Myself, I prefer hard line connections, rather than hoses and clamps. There are also plenty of coolers now that have integrated electric fans with them.
 
Another important thing is to thoroughly flush both your transmission lines and radiator cooler. You can even plumb an in-line filter to catch any circulating contaminants for the first few hundred miles.

On my '68, I ended up running a pair of stacked plate coolers in series, because of the limited amount of room behind the grill. Make sure you use double clamps on all the rubber lines and dedicated transmission fluid hose. I like the fuel injection clamps better than the traditional hygear style clamps. They don't cut into the rubber line as bad.

I also added a pair of ball valves to the lines feeding the radiator and plate coolers(to warm up the fluid for daily driving) and the plate coolers( to allow me to switch fluid flow to bypass the radiator cooler and to only flow to the plate coolers when racing).
 
I just though of 2 more questions:

Does it matter which transmission line I use to go through the cooler? If so, which should I use? The hard lines are as they were from the factory at the bottom left and right.

I've read that is doesn't and some say that it does.

And does someone know what size fitting I need to buy to go into the radiator?

Thank you all.
 
If you have a clutch fan, Ima thinking in California, it should be a thermostatic type. I have not had any success running a straight viscous coupler. The T-type will keep your water temp at a constant temp, assuming it is capable of doing that. The viscous alone will not do that.
Consider this;
Running the temp sender divorced from the water, like it appears you are doing, will introduce a false security. Divorced, it sits in a pocket of stagnant water and the brass fittings are huge radiators. It could be reading waaaay low.
The factory sender appears to still be there, and that one is right in the hot water.If you have an auxiliary gauge, it too should be in the hottest part of the intake,just below the thermostat.
If I had to, I would eliminate the slowpoke factory sender and put the aux sender there... even if I had to drill and tap for a larger sender.
You should only need an aux cooler if running a non-stock-318 Convertor (which were about 1800s), and only if the cooling system is not running at a controlled, semi-constant temperature. Once warm, my system with a T-clutch, a 7 blade all-steel high-attack fan, and an ancient factory rad, runs at a constant 206, plus or minus just a tic, as measured by an IR gun. However our hottest summer days are only maybe 98*F, and I run above-hood,fresh air to my carb.
Altitude will make a difference too, as will ignition timing..
 
AJ/FormS said:
If you have a clutch fan, Ima thinking in California, it should be a thermostatic type. I have not had any success running a straight viscous coupler. The T-type will keep your water temp at a constant temp, assuming it is capable of doing that. The viscous alone will not do that.
Consider this;
Running the temp sender divorced from the water, like it appears you are doing, will introduce a false security. Divorced, it sits in a pocket of stagnant water and the brass fittings are huge radiators. It could be reading waaaay low.
The factory sender appears to still be there, and that one is right in the hot water.If you have an auxiliary gauge, it too should be in the hottest part of the intake,just below the thermostat.
If I had to, I would eliminate the slowpoke factory sender and put the aux sender there... even if I had to drill and tap for a larger sender.
You should only need an aux cooler if running a non-stock-318 Convertor (which were about 1800s), and only if the cooling system is not running at a controlled, semi-constant temperature. Once warm my system with a T-clutch and an ancient factory rad, runs at a constant 206, plus or minus just a tic, as measured by an IR gun.
Click to expand...

I am running both the factory temp sender and a aftermarket temp gauge (bosch). With that intake it is difficult to run the aftermarket gauge anywhere else or in another manner without major alterations to the intake (LD4B) I'm running a stock converter.
 
The transmission cooler is great. Personally I don't run it through the hot radiator anymore I just run it through the auxiliary cooler only.
It's extra added Insurance to keep the transmission cool for the transmission Rebuilder not to get it back. Kind of like you paying for their peace of mind...
In the end it's good to have...
 
FWIW, I just got rid of a tube&fin cooler and replaced it with a stacked plate cooler (B&M Supercooler). I'm running a 3000 stall TC, which heats up pretty good, but the difference was being scared of stopping at a red light vs. wondering if the Tranny Temp gauge was still working because the needle wasnt moving above 140. They cost a little bit more, but the performance of a stacked plate cooler is significantly better.
 
For usually less than $100, a trans cooler is one of the best investments you can make. I put them on about every car I own. Excessive Heat is the enemy of transmissions.

What I do is take off a trans line and use the hose from the kit to plumb them both in a bucket. Have someone start the car for a few seconds & see which hose the fluid comes out. The one that the fluid comes out is the feed & hooks up to the radiator. The added cooler should always be last, as stated above.

I usually buy the biggest one I can fit in the space.

You can try this experiment if you don’t have a trans temp gauge. After driving your car around for awhile, reach under and touch the trans pan. You may burn your hand. Put your cooler on it and try it again. It will just be warm.

There are different types and sizes with varying efficiency, but anything will be a big improvement.
 
You want the radiator plumbed inline first to aid in fluid warm up. Trans fluid works in a temp range. There is a thermostatic block that you can set up to route through the radiator only then open the second loop at a certain temp.
 
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I know I'll be flamed for saying this.
But here it goes any way.
  • Do you tow a trailer with your car?
  • Do you drive up the grapevine daily?
  • Do you have a highs converter?
If the answer is no then the stock fluid to fluid heat exchanger in the rad will do just fine for another 150,000 miles.


Flame away :thumbsup:
 
there's so much more available now than even 30 or 40 years ago. Those trans temp activated valves used to be exotic aviation/high-zoot racing stuff. Now you can order them from Jeg's /Summit. Many of the extra capacity/deep tranny pans have bungs for temp senders, and there are all sorts of trans temp gauges available, too.
 
Dana67Dart said:
I know I'll be flamed for saying this.
But here it goes any way.
  • Do you tow a trailer with your car?
  • Do you drive up the grapevine daily?
  • Do you have a highs converter?
If the answer is no then the stock fluid to fluid heat exchanger in the rad will do just fine for another 150,000 miles.


Flame away :thumbsup:
Click to expand...

I agree but also believe, why not. Right? It's a pretty inexpensive precautionary part. And to answer your questions:
  • No
  • No
  • No
We do have tremendous amounts of traffic at times and from now until October it won't be unusual to have constant 100+ degree days. This is my sons daily driver and although he doesn't go too far, he is on the freeway constantly.

I don't have a trans cooler in my 69 Camaro and it's built similarly to the Dart as far as more of a driver but it only goes to work, car show and coffee and car meets. I would just like to prevent any preventable damage.

Thanks to everyone and all the information!
 
I'm a So Cal native, used to drive the 91 from Anaheim Hills to the 55 to the 22 to the Block in Orange ( or what ever it is called now (17 miles and 45-60 minutes) I got you on the traffic.

BUT... the trans is supposed to run in a temperature band like the engine and if you add an external cooler you might over cool it and lower its normal operating temp. ( thermostatically controlled by-pass would be a good option) Thus making the clearances off which could actually do damage.

Engineers worked out the thermodynamics of the systems and came up with the needed cooling in most areas and conditions.

I'm not completely saying don't add a cooler, BUT as my dad used to say " The parts you don't add don't cause you no trouble" He also said "follow the KISS principle" (Keep It Simple Stupid)

Good luck to you.
 
Dusterdenovo said:
FWIW, I just got rid of a tube&fin cooler and replaced it with a stacked plate cooler (B&M Supercooler). I'm running a 3000 stall TC, which heats up pretty good, but the difference was being scared of stopping at a red light vs. wondering if the Tranny Temp gauge was still working because the needle wasnt moving above 140. They cost a little bit more, but the performance of a stacked plate cooler is significantly better.
Click to expand...
That is what I use with AN fittings
 
I always run the lines like this: into the cooler, out of the cooler, into the rad and out of the rad back to the trans. I let the rad finish cooling the fluid as the trans needs some heat in it to work properly. Kim
 
oldkimmer said:
I always run the lines like this: into the cooler, out of the cooler, into the rad and out of the rad back to the trans. I let the rad finish cooling the fluid as the trans needs some heat in it to work properly. Kim
Click to expand...
Loose convertor , that`s *** backwards ----
 
I do not use the cooler in the radiator, I have seen them go bad and mix ATF with coolant. So I run a good trans cooler , in front of the radiator. Usually the B&M stacked coolers with pipe threads.
 
I had just the stacked cooler on my car. The trans seamed to get hot after three runs and flare in RPM's going into drive. Because I had to order a new Be-cool rad for the car. I ordered one with the cooler. I don't have to hook it up if I don't want. But its there if I need it.

I did not have a trans temp gauge nor did I have my digital thermometer. so I am not sur of the temp. I do have this video of the trans shift when hot. The trans would only do this after three 1/4 mile runs. Leave it cool and it was good.



Here it is a couple of runs prior colder.

 
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Right or wrong, I ran only the B&M stacked plate cooler without the radiator loop. 904 Manual V/B behind a 340 all around Clearwater & Tampa stop & go for years with zero problems.

EDIT: I think it was/is the 15,000 BTU unit IIRC
 
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RogerRamRod said:
Right or wrong, I ran only the B&M stacked plate cooler without the radiator loop. 904 Manual V/B behind a 340 all around Clearwater & Tampa stop & go for years with zero problems.

EDIT: I think it was/is the 15,000 BTU unit IIRC
Click to expand...
I can believe that I only ever ran a cooler. But I believe foot braking the car with a 5500 stall was getting something hot.The trans never flared like that until we would go rounds in a row.
 
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