Can I run a trans cooler independently of the radiator system?

[ubtripn]

I am going to go for the install on my 700R4 but would like to run the trans cooler on it's own system independent from the radiator, perhapsd like an additional, little radiator or something so I don't ever lose another tranny like I did before. Is this possible> If so, has anybody done it?

[Todd68Chevy]

Yes the cooler can be independent. Here are some choices I found with a quick search. http://www.jegs.com/webapp/wcs/store...mission+cooler I am sure there are other options out there. Most of your local part stores and business that deal with hitches/ trailers sell them. They are usually used on trucks that tow for extra cooling. You can buy them as a kit and they should have instructions in the box. Most of them just attach to the front of the radiator or a/c condensor and use the engine fan to get the air to cool it. Some people do not like the look of them out front so on page 2 of the link I show is also an option that has its own fan and can be mounted under the vehicle. I have a buddy that has a Model A that he races and he has 2 of the B&M coolers with built on fan and has them mounted under the car in the rear.

[ubtripn]

Thank you so much, that is a really great response and gives me exactly what I need. See, I had a GMC (late 90's) and the antifreeze found it's way into the trannny and I lost it, so I don't want the two system connected in any way, thanks again for all of the information!

Just out of curiosity - how does the fluid flow, is there a seperate pump or something?

[Andy4639]

The trans cooler is just that. It's built to cool the transmission weather you plum it into the radator or not it will work. I perfer it being inline with my radator my self.

[ubtripn]

Wow, I didn't know that I could not plump it to the radiator and still have the coolant flow. I had figured on a sepearate pump of some kind. I am going this route so I just never have that happen again. I almost lost my enigine as well since there was tranny fluid mixed with the coolant.

Has anybody else ever had that problem happen? Am I over reacting by going this route? Mayebit was a one in a thousand fluke or something.

[Andy4639]

The transmission is what pumps the fluid. That can happen I guess, I never have seen it though!

[cdowns]

main problem with not using the radiator heat exchanger method is you can actually overcool the fluid as the tranny works best and most efficently at a specific temp

[ubtripn]

Yikes, I never figured on a tranny having an optimum operating temp. Dang, now I'm not sure what to do.

I am sure glad to have all the input though.

[Todd68Chevy]

I have worked in dealership and repair shops for 22 years and it is pretty rare for the transmission cooler to crack and mix the 2 fluids but it does happen. The cooler is a seperate item that is just located in the radiator. Back when radiators could be fixed they would just take the tank off and replace the coolers and reassemble. Usually if it is caught quick enough the worse thing that happens is the coolant hoses get weak from the oil and expand or start leaking. If it goes long enough to get coolant in the oil it will destroy a transmission. The transmission works at a higher pressure so more trans. fluid goes into the coolant. After the engine is shut off and the transmission stops building pressure and the cooling system still has pressure is when the coolant goes into the transmission cooler. A lot of times when a transmission fails and has a lot of debris trough out the cooler can not be cleaned out so the transmission shops will add an external cooler to keep the debris out of the new transmission. New trucks with a tow package use the radiator cooler and then also have a factory installed external cooler for extra cooling. If you look at almost any street rod you will not see a cooler in the radiator but they have to have one somewhere. Like Andy said the transmission has the pum and supplying flow so it does not care where it goes but heat is the worse thing on an automatic transmission.

[Todd68Chevy]

Originally Posted by ubtripn

Yikes, I never figured on a tranny having an optimum operating temp. Dang, now I'm not sure what to do.

I am sure glad to have all the input though.

If you use the radiator cooler either go with a new radiator or if you still have a radiator shop in your area have them install a new cooler in your radiator and then you are not dealing with old parts that might fail.

I also forgot to say that when you use the coolers with a built on fan they sell a temp. control fan switch that you can install and then the fan is only running when the transmission temp. shows it needs the fan.

[AusTx68]

I mounted a heat sink cooler to the front of my crossmember and bypassed the radiator all together. I wouldn't recommend this setup if you have a daily driver and live up north. It works fine for me in Texas.

[ubtripn]

Thanks Todd68 and all, that is alot of good information. Now I have a bunch of thinking to do. I could just install a new radiaor and plumb the tranny to it since I won't be doing much towing but in Boise, ID the temps can get up there in the summer so I am not sure about adding an additional cooler.

Sounds like the best plan though is to do just that. New radiator, plum a transcooler in line with it then I am ready for anything that I have to do and it is installed correctly the first time.

(I did wonder why there are not air cooling fins on the tranny, I guess the real heat is deeper inside. IAre the heatsinks plumbed to the tranny?)

[ubtripn]

Originally Posted by Todd68Chevy

A lot of times when a transmission fails and has a lot of debris trough out the cooler can not be cleaned out so the transmission shops will add an external cooler to keep the debris out of the new transmission. .

Sorry Todd68, one more stupid question, in the above statement - does this mean when they add a cooler it is indeed independent of the radiator?

[Todd68Chevy]

Originally Posted by ubtripn

Sorry Todd68, one more stupid question, in the above statement - does this mean when they add a cooler it is indeed independent of the radiator?

Yes they bypass (do not use) the radiator cooler so the debris does not come out of it and get back into the new transmission and damage it. I am not saying this is the correct way or best way I am just saying that some shop do it.

If you use an external cooler and want to paint it so it does not stick out (most are silver) try to find radiator paint or some type of paint that lets heat thru. It lets the heat thru where regular paint will not let the cooler disapate heat as good as it should and may restrict air flow also.

On the 46 that I am building I am going with the external cooler with its own fan and temp. switch to control it because the aluminum radiators they sell for them does not have a cooler in them.

Hope this helps you and not confuse you. Good luck on your project.

[ubtripn]

Thanks a ton! You have been a huge help!

[stich626]

it gets cold here, so I run it from tranny to extra cooler then to cooler in radator then back to tranny,, over cooling can do as much damage as over heating the temp shock to the parts will make them fail sooner than later