Fly-half Frederic Michalak weighed in with 19 points from five conversions and three penalties, and flanker Alexandre Lapandry added a late sixth try as the French exacted sweet revenge for their narrow 23-20 defeat in the first Test.
Centre Maxime Mermoz, Huget and Lapandry went over in the second half.
The half-backs plus Fall and Mermoz were brought in by France coach Philippe Saint-Andre after his team succumbed to a late try in Cordoba last Saturday.
Pumas centre Felipe Contepomi kicked a first half penalty and converted flanker Tomas de la Vega's late consolation try two minutes after France replacement front-rower Christopher Tolofua was sin-binned.
Contepomi, who played his last Test as captain but may play the inaugural southern hemisphere Rugby Championship later this year, took his Argentine record points tally to 628.
The French victory, their first in Argentina for 10 years, levelled the two-match series and left the Pumas to ponder an error-riddled performance after having won their first two matches of the June Test window. They beat Italy 37-22 two weeks ago.