Transmission Cooling Lines

[DavidJBlythe]

Gentleman,

Does any one know the direction of transmission coolant flow through the radiator? I'm installing a temp gauge on the intake side, and a large in-line cooler on the return side. I tried to let the truck warm up and feel the lines, but it started raining on me.

There are two metal lines, connected on the driver's side of the radiator, one over the other. Which is the IN and which is the OUT?

I did check the manuals, 20 and 34, but didn't see a clear answer.

-David

 

[DavidJBlythe]

John,

I haven't had to post an ad yet, but I do believe there is a some kind of minimum participation required in the forums required before you are able to. I wish I knew more to tell you, but that's it.

-David

 

[Chief_919]

You need 100 posts before you can post an ad.

 

[DavidJBlythe]

Any word on the original post, I don't want this to get off-topic.

 

[Chief_919]

The bottom fitting on the transmission is the "out" line, just follow it up.

 

[DavidJBlythe]

Awesome! Thanks for the information.

 

[hvnbound]

classified ads

Chief 919,
Thank you for the reply. Could you direct me to those rules? Appreciate it !

 

[Warthog]

please stop hijacking someone else thread.

The rules where part of the sign up process. It is also at the top of the page under "Forum Rules"

You have to be a member and have 100 "usefull" posts before being allowed to post an ad. And it has to have a Moderators approval

 

[Recovry4x4]

In reference to the lines. If in doubt, start up vehicle and hold both lines. The one that heats up firstflows towards the rad.

 

[DavidJBlythe]

I confirmed that on my truck, the return line to the transmission was the top metal tube from the radiator.
Using a brass T-block w/ 3/8" barbs, I fashioned a temp gauge on the bottom line on the radiator (OUT from Transmission, IN to the radiator). I also cut into the OUT top line on the radiator (RETURN to Transmission) and put in a large transmission cooler.
While driving to Advance Auto for more transmission fluid, I watched my two temp monitors closely. The radiator stabilized at it's normal 170 degrees, and the transmission went to about 130.

I can post pictures for the forum if anyone wants to see where I cut into the lines and what it looks like.

Total cost:
$49.99 for a 15x20" transmission cooler kit. (Advance Auto)
$10.00 for barbs and brass t-fitting. (Lowes)
$17.99 for Temp Gauge (Advance Auto)

I also confirmed that the OUT line on a TH400 is the bottom metal tube on the actual transmission. The RETURN is the top.

 

[Recovry4x4]

Pics are always nice. I need to add the cooler and gauge as well, I'm about to commence the 700R4 swap. I'm also considering plumbing in an extra inline spin on filter.

 

[DavidJBlythe]

Does anyone know the max recommended operating temp of a TH400?