Coolant/ATF question

[AMC]

First off, this is a great resource...thank-you!

Now to the issue. My rig is a 2000 v6 ohv 4x4 stock unit. Bought it 3 years ago with under 70,000. It now has only 82,000. Decided to tackle maintenance items. The one I was doing yesterday was dropping the tranny pan, replacing the filter and adding a drain plug. Everything went fine. There is also an inline transmission filter that I was changing. It's down wind from the lower 5/16 tube on the radiator. The tube was loose and naturally I wanted to tighten it. I also needed to shorten that tube so my new inline filter would fit better. So, I took a wrench and secured the large nut (on the radiator) that the 5/16 tube screws into. Removed the tube and got some ATF flowing out. All normal so far. Now here's the issue...The nut that is in the radiator (that the tube screws into) I removed so I could clean it up and the surrounding area. A few minutes after removing it about 1/2 cup of nice green coolant flowed out. I'm hoping the nut I removed, when in place seals off some port between the two fluids. Please!!! Or do I have a bad radiator?

Also regarding that nut, should there be some kind of gasket or thread loc/seal on it?

Thanks.

AMC

 

[Carguy3J]

There should be no mixing of atf/antifreeze. You either cracked the plastic tank when you removed the nut, or the trans cooler tubing inside is comprised and letting coolant in the.trans cooler. Either way, you would need a new rad. Of course, I would check to make sure it isn't just dripping from somewhere external first.

 

[1Aauto]

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