I’m just about ready to drop my engine in the car. But first, I need to finish running my transmission lines. Routing will go from the trans to the radiator, to the auxiliary cooler, and back to the trans. Full disclosure, the auxiliary cooler is being mounted in front of the radiator. But what exact spot is best?

I have the Hawks ram-air boxes and have gutted all restrictions in front of the radiator. Should I place it in front of one of the fans? If so, which one? Doesn’t one run constantly and one kick in at the designated temperature? Not sure yet but feel free to let me know if you know that one.

Or, should I put it directly in the center of the radiator, essentially between the two fans? See pics below for reference. Any help is appreciated. Thanks in advance.

 

Trans needs to stay cooler than radiator so keep it away from the radiator and avoid mixing with radiator heat.
Radiator is often 200*F~ Engine coolant should be leaving the motor around 212*F to 220*F
Trans needs to stay under 175*F 180*F max for lifespan

I prefer to use a high quality trans cooler with a fan in the rear of the vehicle. Using creative duct and mesh to prevent debris and direct some airflow, fan does most of the work though.
Otherwise I will look for a location to the sides, away from radiator and intercooler stuff off to the side. Use a good cooler though, the one in your pictures is average or below average. If you have a serious transmission build and especially high stall it will take a superior cooler to maintain 155 to 175*F ideal temps for long abuse

 

Since you've got those scoops in there, it looks like the cooler will be partially obscured from the front regardless of where you put it. Therefore, I think most placements in front of the rad should perform about the same.

 

So the trans is a Performabuilt Stage II and this is the cooler they sent. Funny thing is, they say in order for the trans to stay in warranty, the lines have to BYPASS THE RADIATOR and go to that cooler ONLY. I thought that was pretty odd but they confirmed that. However, I am running a brand new radiator and in that case, they said it was fine to run in series. Series seems like it would cool best. But yes, this is the cooler they sent.

 

All I can say is, watch the temp and if it goes over 175*F You gota upgrade or do something about that, heat kills





I keep mine 155 to 165, warning lamp at 178*F in the pan, fan goes on 168*F on the cooler

 

In series works best. I tow with a 2,800 stall and even with a big 40K trucool as a standalone cooler the 4L85E will overheat. Put the fluid to fluid cooler in the loop and my transmission runs 30°F cooler. I actually removed the 40K and put a M7B in its place. The M7B cools great plumbed inline after the radiator. In radiator followed by the M7B cools alot better than the 40K and reduces the heat dumped in front of my ac. I like my 38°F center vent ac temps at idle in 102°F heat. Eliminating that 40K was a win win for me. Cooler trans temps with the factory cooler and smaller auxiliary cooler and better ac. The cooler side of the radiator is far below the 200-220°F of the engine. In my case the engine never gets hotter than 185-190°F. My cooler side of the radiator never sees 160°F and is much lower going down the road.


M7B directly under the hood latch in the center of the grille opening. 16" puller mounted directly behind it behind the radiator. Sorry about the gauge set in front of the cooler. Was the only decent picture I have of the cooler plumbed up.

Have a PCM controlled 16" 3,000 cfm Flexalite right behind the radiator in front of the mechanical fan. Shroud off for the picture. The electric fan is enabled with the ac at 90°F engine temp(so that it comes on with the ac on a hot day), at 185°F engine temp without the ac and then only under 25 mph. Above idle the mechanical fan is more than capable of moving all the air it needs.

 

Upgraded cooler has arrived!!





Now I can brace it and run the lines.

 

It’s mounted. All I have to do now is finish running the lines to and from it.

 

Do you have anymore Images of the Aluminum Structure and Ducting that you created?

I really like what I have seen thus far, great job!

 

I would flip the cooler around and turn the fan into a pusher

The way you have it now will create turbulence between the rad and cooler
Whereas if the cooler can press up against the rad, airflow from the cooler can continue on through the rad quickly without inducing turbulence

 

The pusher setup moves less air and will block alot of the ram air effect though the cooler. Really its half full or half empty. Personally I don't run a fan on my trans cooler. The pusher I ran numerous years back actually increased the trans temp on the highway and did not really make a difference at slow speeds. The clutch fan was more than capable of pulling strong airflow through it. My newest setup has a 16" puller behind the radiator, in front of the clutch fan. Trans cooler sits right in front of the fan with the condenser sandwiched between the cooler and radiator. 4L85E stays very cool.

 

Half full is having the fan but not needing it.

I run 4l80e, 600rwhp using trans cooler placement in front of radiator for 4 years. Max temp 165*F driving 1 hour in traffic. Cooler has fan that comes on 175*F as a pusher. But fan does not come on normally unless I run the vehicle very hard frequent back to back after few hours of traffic on very hot days.

On side note the trans used to warm 180*F before rebuild. I perform Lube-to-Line mod to reduce temps since then 165*F normal.

 

Here’s a few more pics.


Here’s the front with and without the grill screens.




Here’s both sides from within. Still plenty of flow to the auxiliary cooler, ram-air scoops, and the radiator.




And here’s a far and close up of the last PTFE connection I need to make. As you can see, there’s still a gap between the radiator and the auxiliary fan. And I’m going to stick with the pull setup. If it doesn’t work out best, I can always flip it.

 

No replies huh?

Well then, question: How should I wire the fan? Splice it with the main fans? Run it separately? And if so, how?

 

I'd run a temperature switch in the trans pan that grounds at whatever temp you want your fluid to be at, and have that trigger a relay with appropriately fused power going to the fan. You can get universal kits with relays and fuses and stuff on summit.

 

I used one of these for years with great success in the pan
ebay # 232606969888
$20 triggers ground for a relay

After a few years I created my own fan controller project using an arduino
https://forum.arduino.cc/t/arduino-n...ions/620615/14

I carefully calibrated the sensor resistance in my lab using 4 scientific thermofisher thermometers and wouldn't you know they all read slightly different temperatures lol






I centered the resistance curve around the important range of temperatures, 160 to 200*F , so it gives up a little accuracy at 100-160 and from 205+ to be more accurate in the range where it needs to be most accurate
curve fitted to an excel polynomial


Polynomial in the code


Little LCD screen tells me the temp and fans ON or OFF.


It also has an alarm music when the temp exceeds set value, and an over-ride switch so I can run the fan whenever I want, and little LED to brightly lit whenever the fan is on to remind me I left it on.

Future plans:
I'm going to add a little blue LED to let me know when the temp is below 150*F also so I can keep track of the trans when its a bit cold.
I'd like a little adjustment **** to vary resistance of the sensor to make it read higher or lower as I please to trigger the fan earlier or later if needed.
And I would like to utilize a true 2-wire 1/8" NPT sensor instead of the garbage $0.05 ebay sensor I have been using- not that there is any issue its just I prefer 2 wire sensors.

 

Awesome. I’ll order some relays and sensors.

Next question: These cars did not come with a transmission temperature gauge. How can I add one? Where would I put the sensor? And where and how would I wire the gauge?