The consulting firm said Wednesday sales of cars and light trucks totalled 167,919 for the month, up from 149,092 in the same month last year.
The gain came as truck sales climbed 22.2 per cent to 100,789, up from 82,497 in September 2013. Car sales amounted to 67,130, up from 66,595.
Sales for the year-to-date are up 5.5 per cent compared with the first nine months of 2013.
"After a slight pause around the New Year, the market has been 'on fire' with this being the sixth month in a row where year-over-year monthly sales records have been set," DesRosiers said in report.
"There were some eye-popping performances at an individual corporate level with 10 vehicle companies recording double digit increases during September," said DesRosiers. Audi led the pack with sakes up by 42.3 per cent, Mitsubishi up by 41.3 per cent, and General Motors up by 34.4 per cent.
The love of trucks helped boost sales of the Big Three North American automakers with Ford, Chrysler and General Motors combining to post a 17.8 per cent increase over last year, according to DesRosiers.
Ford Motors claimed the top spot as Canada's best-selling automaker with a 4.6 per cent jump in total sales last month — its best September on record.
The company said it sold a combined 27,161 cars and trucks last month, compared with 25,956 a year ago.
Ford said sales were driven by its Escape and Explorer models, which climbed 26 per cent and 31 per cent.
"As we head into the fourth quarter, 2014 is proving to be a very strong year for auto sales — the industry certainly is on track for a record-breaking year," said Dianne Craig, president and CEO of Ford Canada.
Meanwhile, General Motors Canada reported sales jumped 34 per cent in September.
The automaker said it sold 24,555 vehicles in last month, compared with 18,270 vehicles in the same month a year ago.
Chrysler Canada also had a healthy increase in vehicle sales, after selling 23,742 vehicles in September, a 20 per cent increase from the same month last year — thanks to the success of its light trucks and minivans.
The company's biggest seller was the Ram pickup, which accounted for more than one-quarter of Chrysler Canada's volume in September.
It sold about 6,590 Ram pickups, up 4.9 per cent from September last year.
Chrysler's various lines of trucks and minivans accounted for nearly 21,180 vehicles, up 30.4 per cent from September 2013. However, Chrysler car sales fell 29.1 per cent to 2,560 cars for the month.
Import nameplates combined for a 8.7 per cent gain compared with a year ago.
Toyota said it sold 16,475 vehicles for the month, up 7.7 per cent compared with a year ago. The gain was helped by a 25.6 per cent increase in truck sales to 8,745 while car sales came in at 7,730.
Sales by Toyota's luxury Lexus brand totalled 1,501, while Scion sales amounted to 359.
Meanwhile, Honda sales totalled 13,341, up from 12,449, according to DesRosiers, while its luxury Acura nameplate had sales of 1,664, up from 1,515 a year ago.