May saw Ford's total sales figures plummet 16%, while General Motors and Chrysler slipped even further, by 27.5% and 25% respectively.
The preliminary J.D. Power results for June show Ford losing 31.4%, GM down 26.2% and Chrysler off 30.1% against June 2007 sales, according to Automotive News.
Total market volume forecasts have been accordingly adjusted, down to 12.5 million total cars sold from 16.3 million at this time last year, and earlier predictions ranging from 15 to 16 million.
Toyota will also see a total sales drop, but at only 6.6% lower than last year, it won't be the nosedive the Detroit 3 are seeing. Nevertheless, J.D. Power's numbers indicate Toyota won't overtake GM in total U.S. sales this month, contrary to predictions by some analysts earlier in the month.
Honda's sales look to be headed up, rising as much as 9.3% over June 2007. The Civic and Accord held two of the the top three spots in overall sales for May, likely due to their relatively high fuel efficiency and reasonable price.