Routing of external trans cooler...before or after rad?

[PaulRV6]

What is the concensus on how the external cooler should be plumbed, from trans to stock rad cooler or external cooler first then to stock rad cooler? Or doesn't it make a difference?

What is the flow of oil out of the trans, the top line on the trans the output or otherway around?

paul

 

[Renthorin]

I don't remember which line is the output from the trans but I do remember it was not the one everyone told me

I took both lines off the radiator cooler and put to empty pop bottles over the ends. Ran the car for a second and noted which one filled.

I then hooked them back up and put the trans cooler 'after' the radiator. I figured I would let the radiator coold down the fluid to as cool as it could... then let the air cooler (mounted in front of condensor) cool it down further.

My assumption is that the air will always be cooler than the radiator so why risk raising the trans fluid back up by warming it in the rad.

 

[bruce]

Originally posted by PaulRV6
What is the concensus on how the external cooler should be plumbed, from trans to stock rad cooler or external cooler first then to stock rad cooler? Or doesn't it make a difference?

What is the flow of oil out of the trans, the top line on the trans the output or otherway around?

For a heat exchanger to work at it's best means having the createst temp delta between what needs cooled, and the cooling agent. So I have fluid routed from the tranny to the air to air cooler, and then to the radiator. I don't see why one would want to put any more heat into the radiator then necessary. With the cooler still being routed thur the radiator in cold weather, the tranny fluid will still pick up a little heat from the radiator. My Level Ten tranny has about 40K miles on it this way, and it still shifts like the day I got it.

YMMV

 

[85 ttypewh1]

Your theory about the heat exchanger is right, but then you do not want to run the fluid back through the rad and heat it back up. If you have a bigggg cooler you can run just that, but if not i would run to the rad then the cooler. It even said that in the instructions i had with mine. Besides that the fluid is already running through the rad so its not like its going to heat the rad any more than it already is. As far as the lines to be absolutely sure disconnect them and see which way the fluid flows. All the ones i have done have been tapping into the top line, but who knows.

 

[Renthorin]

I 'think' mine is the top line too but like I said, do the pop bottle test

 

[bruce]

Originally posted by 85 ttypewh1
Your theory about the heat exchanger is right, but then you do not want to run the fluid back through the rad and heat it back up

Normally the tranny fluid is warmer then the coolant, so it'll be sheding heat into the radiator, other then when the engine is cold. You can run ATF too cool. The tranny assembly tolerances are for a *warm* tranny. If you want to start to run really cool tranny fluid, then you might have to adjust the clearances. At freeway speeds, things aren't as critical as around town, and stop and go traffic, IMO. At decent road speeds there's enough air flow for the tranny cooler, and radiator to easily do their jobs. It's the hot weather, stop and go, or making passes back to back that play havic with the temps., from what I've seen.

 

[85 ttypewh1]

Bruce, that is my problem i live in texas and have a drag strip 5 miles from my house, too hot and to many reasons to race.

 

[PaulRV6]

I really can't run the engine yet but I did want to get the cooler lines routed correctly prior to starting it. Where can I find out which way the fluid flows from the transmission connections. One of our tranny experts must know, its not like the fluid flow can be different on the 2004r's right? Thanks for the info.

paul

 

[77 cruiser]

not an expert

The top line on the trans is out.

Jim

 

[GNVYUS 1]

I put mine after the rad because it was easier t install and ambient temps are cooler than a 180 degree rad.

I am going to run two air/air coolers when I ditch my stock rad for the Summit aluminum rad. I am going to run a temp gauge before the mod to see if there is a difference in temps. I bet two air coolers/no rad is better than rad/air cooler.

 

[2quiktocare]

The top line on the trans is the outlet, bottom is inlet. Run the fluid thru the radiator first, then into the external cooler and then return to the transmission.

 

[PaulRV6]

Thanks to everyone for your great help. I have clear direction on how to hook it up.
Now I just need to find a 5/16" male inverted flare with a 5/16 or 3/8" barbed end, or an inverted flare male union. These are no where to be found. Any ideas?

Thanks again, paul

 

[Matt Sando]

Pep Boys has thee brass fittings

 

[V6UnderPressure]

A while back I asked the question about routing the transmission lines for an external transmission cooler. I have done a search and half say that the upper line on the radiator flows to the transmission and that the bottom radiator fitting is coming from the transmission, and half say that the fluid comes from the transmission into the top of the radiator and comes out of the bottom of the radiator back to the transmission. Does anyone have the EXACT correct answer to this?

Scott

 

[NCC1701]

tranny cooler lines.............

The bottom cooler line on the radiator is the inlet from the transmission, the top cooler line on the radiator is the outlet back to the transmission ( or external cooler if deired).
The top port on the tranny is the outlet to the tranny cooler, the bottom port on the tranny is the return from the tranny cooler.
They are counterintuitive
top port on tranny to bottom inlet at tranny cooler, top outlet at tranny cooler to bottom inlet port at tranny.
HTH
Lorenzo

 

[MCH86GN]

tranny cooler lines.............

The bottom cooler line on the radiator is the inlet from the transmission, the top cooler line on the radiator is the outlet back to the transmission ( or external cooler if deired).
The top port on the tranny is the outlet to the tranny cooler, the bottom port on the tranny is the return from the tranny cooler.
They are counterintuitive
top port on tranny to bottom inlet at tranny cooler, top outlet at tranny cooler to bottom inlet port at tranny.
HTH
Lorenzo

Wow, I seen a picture from a manual and it has the top port of the transmission to the top of the radiator and bottom port to bottom. If your car is park will transmission fluid still flow? Because that seems to be the only way to know for sure. My brakes don't work at the moment so I can't shift into gear without fear of grinding the transmission. I had my transcooler connected up and now because of what I have read I changed and in the interim more or less rendered one of my transcooler lines useless, if I need to connect it back to the transcooler.

Unless I'm mentally challenged and discern what you said. I have even drawn a picture. Today, when I get home I will turn my car on and put a catch bucket and confirm flow. That is if trans fluid flows in park. I have no brakes, so I won't be able to put the car in drive, that includes an e-brake. Car is hoist

 

[MCH86GN]

well

bumb ubm!

Well I took two cans and took the lines off and placed them in the cans and had my wife start my car. I got my answer. The top port on the radiator is the return line to the transmission, so that fluid is the cooled fluid which gets cooled again by the trans cooler, but like a dumass I connected the lines to and fro the cooler wrong. Got it right now. I now have to take the hose off the top hose connector. That is not going to be easy, because I just put the air bafflers and they are tough to work around.

Oh and from the transmission, I don't know how the lines are connected. I will need to replaced the return one because I bent the hell out if and the flare nut won't even move without used channel locks and turning them.

 

[Turbo Loyd]

If you ever plan to drive the car in cold weather put the air to automatic transmission fluid heat exchanger first so the fluid can warm back up in the engine coolant to automatic transmission fluid heat exchanger in the radiator. As mentioned above you can cool the automatic transmission fluid too much.

 

[huntsg]

I have a FMIC and I'm getting ready to install a trans cooler. Any suggestions on a location for the cooler? I'd rather not put it in front of the radiator. Thanks.

 

[MCH86GN]

tranny cooler lines.............

The bottom cooler line on the radiator is the inlet from the transmission, the top cooler line on the radiator is the outlet back to the transmission ( or external cooler if deired).
The top port on the tranny is the outlet to the tranny cooler, the bottom port on the tranny is the return from the tranny cooler.
They are counterintuitive
top port on tranny to bottom inlet at tranny cooler, top outlet at tranny cooler to bottom inlet port at tranny.
HTH
Lorenzo

With regard to the configuration you suggested, with the top and bottom of the trans cooler lines is correct. So the stock configuration, top line from the transmission to bottom port of the radiator. Then the top port if the radiator output to top port of transcooler and the bottom port of the transmission cooler to the return line of the transmission.