Automakers posted sales gains in May, but mostly missed analysts’ sales growth forecasts.

Chrysler, owned by Italy’s Fiat, reported that it sold 150,041 cars during the month, up 30% from 115,000 in May of last year. Still, that fell short of the 40% increased analysts were looking for, Bloomberg said.

Chrysler noted that Jeep sales rose 24% compared to the prior year, while Chrysler-branded vehicles spike 80%.

General Motors (NYSE:GM) said it sold 245,256 vehicles for the month, up 11% compared to last year. That missed analysts’ prediction of a 15% sales increase.

Japanese automakers also posted better sales. Toyota (NYSE:TM) announced that May U.S. sales spiked 87% to 202,973. That disappointed analysts who had estimated a 93% gain as the company continues to recover from last year’s natural disasters in Japan.

Nissan (PINK:NSANY) posted a 21% increase for the month, selling 91,749 vehicles, but fell short of analysts’ forecasts of a 29% rise.

However, Ford (NYSE:F) bucked the trend of missed estimates. The company sold 215,699 cars and light trucks during the month, up 13% over the same time last year. That narrowly topped the 12% gain analysts expected.

Analysts cited by the Bloomberg said automakers might have to rely more on incentives to attract consumers in coming months as the demand to replace aging cars held through the recession slackens and economic worries increase. Both GM and Ford have promoted rebates and discounts on selected models.