trans cooling?

[david1938]

I would like some advice. After Mr. Patton instructions on changing the trans

fluid and a lot of procrastinateing, I did it. But I think there is a problem. I did not know which is the inlet or outlet. So after a long run, I climed under the truck

and found out the line closest to the engine was a lot cooler. This is the return right? ok, disconnected it, put a hose on the return line started the engine and the fluid came out. But not the hose, from the transmission and on me.

Daughter shut the engine off. So my question is, why is the fluid much hoter

going in the trans. Is something wrong?

 

[JBallou]

The cooler / heater on the side of the block is what is doing it. The cooler is also connected to the coolant system. In cold weather it heats the trans fluid up to engine temp, if it gets over that, heat is transfered back into the coolant. Works both ways to stabilize the temps.

 

[david1938]

ok, thanks a lot, that helps

 

[cerberusiam]

I think you disconnected the cooler output line.



Cooler output is the front line fitting on the trans (closest to the engine), cooler return is the rear line fitting on the trans.



Disconnect the rear line and route the line output into a container to do a fluid exchange.

 

[david1938]

I did that, and it did work much better and I changed all the fluid. it now is clean

fluid, and does not have the burn small it had. now I am trying to figure out how to add

a transmission cooler in front of the ac cond. then run lines to it. Not much room in front

of the ac cond.

 

[cerberusiam]

now I am trying to figure out how to add
a transmission cooler in front of the ac cond. then run lines to it.

You already have a large air to fluid cooler that is very efficient right in front of the radiator. There is no need for additonal one at the front.

Adding additonal coolers to the stock system needs to be approached with care. The OE design of coolers and even fluid temp is created for optimal flow. As the cooler return is the main source of transmission drive train cooling and lube flow, changing it can have some reprcussions.

Without making other changes, one does no want the fluid temp too low or the restriction too high on the cooler circuit. The whole circuit is flow based not positive pressure so even little things can cause issues. Point in fact the drain back check ball and front cooler thermostat will cause heating issues. Once these little oddities are addressed you really have to abuse the trans to get it very hot and then all it take sis locking the TC to cool it down.