Ford alone of Detroit's Big Three saw sales plunge in May. The Blue Oval's volume fell 11.7% to 250,425 units. In contrast, General Motors' sales rose 5.4% to 371,233 while Chrysler inched up 0.2% to 199,393.

Year to date, all three Detroit-based automakers posted lower sales - Ford is off 12.3% at 1,099,209 units, GM sales are 3.2% lower (1,577,912) and Chrysler is down 1.5% at 929,746.

Chrysler, soon to be under new private-equity management was upbeat, however.

"Chrysler Group increased overall sales in May based on a strong retail performance and while fleet sales were down," said US sales chief Darryl Jackson. "Especially our new offerings in the car segment continued to gain momentum, supported by the fuel economy message of our 'Maximise Your Miles' programme. Driven by models like the Chrysler Sebring, Dodge Avenger and Dodge Caliber, the company's car sales increased 15% over the previous year."

The automaker added that it finished the month with 479,501 units of inventory, or a 63-day supply, down 19% compared to May 2006.

"Our May results were extremely positive as we saw strong total and retail sales increases. Our significant market share gains in full-size trucks and crossovers validates the decision we made to invest in industry-leading fuel economy in these important segments," said Mark LaNeve, vice president, GM North American sales, service and marketing.

Toyota reported all-time best-ever sales of 269,023 vehicles for the month, an increase of 9.7% over May 2006. Year to date volume is up 8.5% to 1,085,335.

"As fuel prices and consumer confidence rose, the industry saw a move to passenger cars, with retail business posting sharp gains over a very challenging April," said TMS executive vice president Jim Lentz.

He added that the US market's appetite for hybrids "continues unabated", with the Prius also establishing an all-time record of 24,009 units, up 184.9% year on year. Year to date, Toyota's US hybrid sales are up 75% to 119,154 units.

The fuel-sipping Yaris subcompact reported an increase of 30.5%, posting best-ever May sales of 10,949 units.

Fuel-efficient product also benefited May's biggest gainer, Mitsubishi Motors, whose US sales rose 11% to 13,651 units. YTD volume is up 18.5% to 57,343.

Sales of the redesigned Lancer more than tripled compared to last May, up 228% at 4,028.

In a mixed month, Honda sales were down 1.4% to 145,367 (YTD: +1.8% to 625,994). But, reflecting the trend to more fuel-efficient cars, Civic sales of 39,993, up 32.6% for the month, broke the all-time record of 36,533 set in August 2001. Civic Hybrid sales of 4,520, up 50.4%, also surpassed the record 4,146 set in August 2005. Record May CR-V sales increased by 35.9% to 19,513 and Fit (Jazz) results of 5,361 achieved a new record.

"Small is big right now," said Dick Colliver, executive vice president of American Honda. "Smaller vehicles have become more attractive for multiple reasons and we expect this trend to continue for the time being."

Sales at Mazda were off 5.7% to 26,788 (YTD: +8.5% to 126,922.

"With continued uncertainties in housing, fuel prices and interest rates, consumers are cautious about big-ticket purchases," said the North American unit's president and CEO Jim O'Sullivan. "For a smaller company like Mazda, these rollercoaster times have more of an effect on us than they might for larger companies, and our sales gains and losses this year reflect that."

Overall, US May sales of 1,555,947 were up just 0.7%, according to WardsAuto.com. YTD volume is down 1.3% to 6,763,748.

Sales of import-brand cars have risen 9.4% to 1,002,255 while domestic brand volume is off 6.6% to 2,191,398.

Import-brand light trucks have made gains of 5.5% to 573,472 while Detroit's volume slipped 1.6% to 2,996,623.

Import brands take the top three slots on the car sales table so far in 2007 (Toyota Camry (171,360), Toyota Corolla/Matrix (165,722) and Honda Accord (153,441), ahead of the Chevrolet Impala (144,541).

In light trucks, as ever, the Ford F-series dominates (290,282) ahead of the Chevy Silverado (265,941) and Dodge Ram (154,143). Toyota's Tacoma is highest-placed import at 8th (77,127).

Graeme Roberts