Pretty sure Dexron III was used as the original fill. You can still buy it, called 'Dex/Merc', or any newer Dexron fluid like V or VI.
If it's empty how many quarts to put in
How many quarts to put in if empty
A drain and fill is 5Qts. Did you remove the pan? Buy enough to refill. Depends on how much is left in the converter and cooling lines. Buy 12-14 qts to do your flush and return what you don't need.
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