Car sales in the U.S. likely went up about ten percent last month, compared to the same month a year ago.
U.S. sales for April will be reported Tuesday.
Analyst Jesse Toprak of Truecar.com says sales would have been better, but the disasters in Japan greatly diminished the supply of car parts, especially for Honda and Toyota.
Both companies have drastically slowed production of cars, and the slowdown could continue through the rest of the year.
Toprak says Japanese car companies typically do well when gas prices increase.
But people may go elsewhere this summer if they can’t find what they want at a Japanese car dealership.
"So the biggest beneficiary of this situation is going to be the domestic Big Three, mostly GM and Ford, and Hyundai and Kia," says Toprak.
Toprak says incentives on small cars virtually disappeared in April, because demand was so high.
Car companies also raised prices on a number of vehicles last month, to keep up with higher commodity costs and higher demand.