By Frank Pingue

TORONTO (Reuters) - Canadian auto sales cooled in March after a solid start to the year, though top import nameplates continued to bolster their market share according to company figures released on Tuesday.

Overall Canadian auto sales slipped 0.5 percent to 150,000 vehicles in March after posting double-digit sales gains in January and February.

"Our forecast is for sales to ultimately come down a little over the rest of the year and finish down about 50,000 units," Dennis DesRosiers, president of DesRosiers Automotive Consulting Inc, said in a note.

"Despite the market being up during the first quarter we, at least at this point, are sticking to our forecast. The next three months will tell the tale."

General Motors of Canada (GM.N: Quote, Profile, Research), the country's biggest automaker, said it moved 30,208 vehicles off its lots in March, a 16.4 percent drop from the same month last year.

For the first quarter, GM Canada said its sales rose 1.5 percent to 83,262 units.

Chrysler Canada sales rose 3.5 percent to 21,745 vehicles in March, which marked the automaker's 20th straight month of higher sales. Chrysler did not give a quarterly sales update.

Ford Motor Co. of Canada (F.N: Quote, Profile, Research) said its March sales fell 1.3 percent to 20,083 units, but rose 3.1 percent in the quarter to 46,870.