Allister Coetzee's side endured a miserable 2016, but now boast four wins from four this year.
The strength, speed and superb handling that has graced great Springbok sides in the past were all present as they dominated against the Pumas, particularly in the scrum.
Elton Jantjies' accurate kicking set them apart from their visitors, while there were first international tries for lively wingers Courtnall Skosan and Raymond Rhule.
Argentina showed moments of promise with scores from Martin Landajo and Emiliano Boffelli in each half, but Siya Kolisi and Pieter-Steph du Toit added late gloss for South Africa.
South Africa will look to maintain this form, but they must back it up when the two sides meet in Salta, scene of a surprise Springboks defeat 12 months ago, next week.
— Los Pumas (@lospumas) August 19, 2017
South Africa looked the more likely in the opening exchanges but they only had two Jantjies penalties to show for their efforts.
The Springboks ran the ball at every given opportunity, with Rhule particularly lively when cutting in off the right wing.
However, after soaking up plenty of pressure and missing a penalty, Argentina recorded the game's first try with a swift counter-attack.
Joaquin Tuculet's sensational break set them going before he offloaded to Boffelli on his shoulder, the winger subsequently placing a grubber kick that Landajo scooped up to score.
Nicolas Sanchez missed the resulting conversion to leave the visitors one behind, but their deficit grew before the break as Skosan broke a challenge on his way to a first Springbok try.
— South African Rugby (@Springboks) August 19, 2017
Penalties were exchanged by Sanchez and Jantjies after the restart but South Africa slowly started to wrestle control back, and 12 minutes into the second half Rhule took the game away from Argentina.
The Springboks worked the ball out to the right before Jaco Kriel unleashed the explosive Rhule, the winger showing electrifying pace to evade the Argentina defence on his way to the line.
When Boffelli went over with 21 minutes remaining - Juan Martin Hernandez converting - a tense finale seemed in the offing, but home favourite Kolisi settled any nerves.
The back-row forward was on hand to cap of another flowing passing move from the Springboks, the Nelson Mandela Bay Stadium rising to salute their local hero.
Substitute Du Toit rounded off the win by burrowing his way to the line to complete a fine outing for the hosts.
Photo Twitter@Springboks. Caption: South Africa celebrate