I own a 94 4x4 automatic 4.3 vortec. I finally saved enough money for a transmission cooler. Does anyone know the transmission oil flow into and out of the radiator? Does it flow from the top line to bottom or the other way around? Installing the cooler in series would provide maxium cooling by returning the coolest oil directly to the transmission.
This site is awesome.

 

Kind of depends on where you live and what you prefer. In colder climates it "tends" to be better having the tranny fluid pass through the external cooler first and then pass through the stock cooler in the radiator. This allows you to have warm fluid during the winters.

The opposite tends to work for those who live in warmer climates that never or very rarely see freezing temps.

Many trucks running around with it hooked up one way or the other. All comes down to personal choice, I guess. Being as I live in the deep, deep south I have my extenal cooler tied in after the stock cooler. Haven't had any problems with it, even when I've been up in Colorado during the winter time.

 

Here is a thread that popped up in a quick search.:
Tranny Cooler Lines - Which is Which?


You can also check out the Tech Article (DIY) section for some pictures of an install I helped another member with.

 

thanks again for all the info.
I should be able to do the install this weekend.

 

Post some pics up after the install. I want to know where you mounted the cooler.

 

Check the thread below for some pictures:
Trans Cooler & Shift Kit Install! by 4lowlife