Could he drain some/all of the fluid and let it sit to see if water separates out?

Where are you located, Knuckleballerr?

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

Air foaming will settle out in 12-24 hours.
Drain a tiny sample off the bottom of the transmission oil pan.

Water foam/sludge is bad, centrifuge or boiling..
IMO if it is coolant the transmission would need a total teardown to wash out all of the sludge.

.

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