Trans cooler in radiator busted and mixing with coolant

jtgf250 · Apr 16, 2017

Dropped the freshly built motor in the truck the other day and went for first start up. Started blowing strawberry milk out the coolant tank. Thought maybe an o ring got rolled when putting together the oil cooler. Pulled apart and checked and all good. Then it hit me when pulling the lower radiator hose to empty the radiator that the mix wasn't dark but more like Pepto. So I pulled the trans cooler line and sure enough the same strawberry milk. Drained the trans pan right away.

Now, whats the best way to flush out the trans? Remove the return line and fill it back up and flush like usual or someone have a better idea.

Thanks In Advance

dmd · Apr 16, 2017

I think the usual way would be best, just like you suggested. Seems to get the old
stuff out so should work for this

fastersteve · Apr 16, 2017

The trans makes more pressure than the radiator, so you only have atf in the radiator, no water in the trans.

After you replace the radiator and top off the trans, flush the cooling system with water and Cascade dishwashing powder, about a tablespoon. That will clean the atf residue out of the cooling system.