It hasn’t been a good year for Japanese automakers, with the Japanese earthquake earlier in the year and more recently, floods in Thailand disrupting production, schedule and plans. All this has certainly lost them a fair bit of ground in terms of sales and expansion.

Toyota, the world’s number one automaker, looks set to lose the most – the company is set to cede the top spot in global new-vehicle sales in 2011 to the resurgent General Motors, according to reports. Toyota was No. 1 for the past three years, but now looks certain to drop to third place after the Asian disasters forced the company to cut production at home and abroad.

GM’s global sales for the January-September period rose 9% on the year to 6.79 million units, and with sales in Q4 on track to outpace the 2.17 million units recorded in same 2010 period, the US automaker’s full-year total is likely to exceed nine million units. This number would be 20% above the figure for 2009, when the company filed for bankruptcy.

Meanwhile, Volkswagen is expected to advance one spot to second place, with group sales surging 14% on the year to 6.17 million units in the first nine months of 2011. In 2010, Toyota and GM were the only carmakers to achieve more than eight million units sold – VW is positioned to reach that milestone for the first time this year, helped by double-digit sales growth in Europe, North America and Asia-Pacific, the reports say.

As for Toyota, its January-September sales slid 9% on the year to 5.77 million units, and with the effects of the Thai floods set to impact the October-December figures, it looks unlikely that Toyota will narrow the gap with GM and VW, which have also enjoyed a head start the world’s largest market, China.

Elsewhere, Hyundai, which surged past Ford in 2010, is on pace to consolidate its position thanks to robust sales in the US, China and other key markets – the company has already upgraded its sales forecast for the full year to at least 6.5 million units, from the 6.33 million units projected, the reports add.