DETROIT -- Ontario surpassed Michigan last year in vehicle production for the first time ever, with record production at a General Motors Corp. and Suzuki Motor Co. Ltd. joint venture and two plants owned by Japan-based auto makers leading the way.

Ontario's success in landing Honda Motor Co. Ltd and Toyota Motor Corp. plants in the 1980s and subsequent expansions in later decades paid off as the province's auto plants cranked out 2.663 million vehicles in 2004, compared with 2.588 vehicles in neighbouring Michigan.

The final numbers were released on the weekend by auto makers and industry publication Ward's Auto World. Previous articles on the topic were based on estimates of production for December. The final numbers show that Ontario plants increased output by 7 per cent from 2003 levels, while production at Michigan factories slid 6 per cent.

With the exception of a single joint venture between Ford Motor Co. and Mazda Motor Corp., all production in Michigan comes from the traditional Big Three producers.

Production at several plants in Michigan fell last year because they were shut down for periods for model changeover, noted Michael Robinet, vice-president of forecast services for consulting firm CSM Worldwide Inc. in Northville, Mich.

But the more important issue, Mr. Robinet said, is whether Ontario can maintain its edge in the face of a continued shift in automotive production from the traditional Ontario-Michigan-Ohio belt to the U.S. South.

"How come there's no Nissan plant in Canada?" he asked.

Japan-based Nissan Motor Co. Ltd. is the only auto maker with an assembly plant in Mississippi.

"The [rise in the Canadian] dollar's not helping keep the edge," Mr. Robinet said in an interview at the North American International Auto Show, where auto makers are showing off new concept vehicles and 2006 model year cars and trucks.

The Ontario production increase in 2004 was led by a 157-per-cent surge to 131,910 vehicles at Cami Automotive Inc. in Ingersoll, Ont. Cami's switch last year to assembling the hot-selling Chevrolet Equinox sport utility vehicle was a key reason. Output should jump even more this year when production of the Pontiac Torrent SUV is added in the spring.

The increase in output at the two wholly owned Japan-based plants was greatest at Toyota Motor Manufacturing Canada Inc. in Cambridge. Workers there built 287,859 Corolla compacts, Matrix crossover utility vehicles and Lexus RX330 luxury SUVs.

Output at Honda of Canada Mfg. in Alliston, Ont., rose slightly to 392,528 cars and SUVs from 392,101, but that was also an annual record.

In Ontario, DaimlerChrysler Canada Inc. also boosted production in 2004 with a 30-per-cent gain. Output should increase again in 2005 with the addition of a third production shift next month to assemble the Dodge Charger, which will be unveiled here at the North American International Auto Show today.

General Motors of Canada Ltd., the largest auto maker in the country, posted a slight decline at 924,000 vehicles.

The biggest decline in output came at Ford Motor Co. of Canada Ltd.

Ford's vehicle assembly fell 19 per cent to 372,241, which enabled Honda to displace it as the third-largest assembler in Canada.