The Kangaroos dominated Sunday's match at Punt Road from start to finish, with the Swans' sole score coming late in the first quarter.
North Melbourne's previous biggest win was their 62-point triumph over Geelong in 2021.
Two goals in the final minute from forward Tahlia Randall ensured the Kangaroos set a new record.
The 9.13 (67) to 0.1 (1) win catapulted North (4-2) from eighth to fifth, and improved their percentage from 132.5 to 189.6.
Randall finished the match with 3.3 from 11 disposals.
Ashleigh Riddell racked up 25 disposals, Jasmine Garner booted 2.1 from 17 possessions, and Garner also tallied 10 tackles in a huge display.
Gowans was surprisingly sacked by North Melbourne in 2020 despite guiding the club to 11 wins from his 14 games in charge.
Although his fledgling and winless Swans were never expected to challenge the powerful Kangaroos, the extent of the defeat was painful.
Sydney were starved of opportunities throughout the contest.
On the rare occasions when they got within goal kicking range, Swans players were tackled to the ground or harassed into making an error.
Kangaroos big Emma King set the tone early with a mark on the goal line, and Riddell had the ball on a string in the first half.
North Melbourne's inaccuracy didn't really matter given their utter dominance.
The only question was whether they could post a club-record win, and Randall stood tall in the final minute to deliver the goods.
North won the inside 50m count 41-17, clearances 27-19, contested possessions 105-84, and hitouts 37-16.
24°C