TH400 Cooler line flow direction

[BigJohnson]

Does the flow direction of the TH400 cooler lines matter if going through the radiator cooler only? I just got finished putting my rebuilt trans in and I had to make new lines. Right now I have the top trans fitting to top of radiator and bottom to bottom. From searching I think this may be backwards. If its just a loop doesn't seem like it would matter but I don't want to ruin my fresh TH400. Any help would be appreciated.

 

[magik235]

The information below is form http://www.tciauto.com/Products/TechInfo/cooler_fittings.asp

TH400
Fitting Location..... Thread Size..... Flow Direction
Upper .................... ¼" Pipe............. Return/in
Lower..................... ¼" Pipe............. Cooler feed/out

I just had my TH350 rebuilt and was told the feed goes to the top of the radiator and the return goes to the bottom. The reasoning was the radiator is cooler at the bottom. I made new lines and installed a cooler when I installed the tranny.

 

[folkenheath]

If you already have it done I wouldn't worry about it, just run it. I have had a TH400 running like that for 12 years, same trans, and it's taken a beating. I have a tranny cooler only in that, no radiator passage.

What's more important though, is to make sure you completely flush the cooler out, so there is no debris from a bad trans in there.

 

[magik235]

NAPA has an aerosol product for cleaning cooler lines. It works good. I used 2 cans to flush my radiator lines then installed an inline transmission filter on my return line.

 

[BigJohnson]

Thanks for the info guys. I think I will run it that way until I re-do the lines. I made them from pre-made lines and didn't really like the way they turned out. On flushing the radiator cooler I just went with a new radiator. Mine was leaking anyway so I opted to replace it so it shold be nice and clean.