This year the percentage of suppliers that are increasing expenditures for the Japanese was down slightly from 2004. But Henke says the fluctuation was not statistically significant.
Based on this two-year trend, Henke says suppliers believe it's more profitable to do business with the Japanese automakers. Suppliers also believe that GM - and, to a lesser degree, Ford and Chrysler - emphasizes cost rather than quality.
According to the survey, 62 percent of GM suppliers said they cut prices because they were threatened with the loss of business. Forty-seven percent of Ford suppliers and 49 percent of Chrysler suppliers cited that reason for price cuts.
By contrast, 24 percent of Nissan suppliers said they cut prices to avoid retaliation. Just 6 percent of Honda suppliers and 5 percent of Toyota suppliers cited that reason for price cuts.
GM spokesman Tom Wickham downplays the survey's conclusion of poor supplier relationships, saying GM frequently consults suppliers on a range of issues.
Ford spokesman Joe Koenig notes that Ford is "actively working with our suppliers to improve relationships."
Henke says Chrysler's relations with suppliers were pretty good, except for one category of components that he declined to identify.
"There is probably still a concern among suppliers whether (Chrysler's changing attitude) is real or not," Henke says. "It may take a while for them to believe it."
Overall, the Big 3 should accept the survey as a wake-up call, Henke argues.
"This data suggest that they have not yet recognized that they need their suppliers' help to be formidable competitors," Henke says. "They cannot do it by themselves."
You may e-mail Robert Sherefkin at