Statistics Canada says manufacturing sales fell 2.0 per cent to $71.6 billion in May as auto production fell in the month.
The agency says the first drop in manufacturing sales after seven consecutive months of gains came as sales dropped in 11 of the 21 industries it tracks.
Sales in the motor vehicle industry fell 31.9 per cent to $3.3 billion in May, due to retooling at auto assembly plants and semiconductor part shortages.
Primary metal sales fell 4.1 per cent to $6.3 billion for the month, but still posted the second highest sales on record after April.
Meanwhile, higher prices helped sales in the petroleum and coal industry rise 5.4 per cent to $10.9 billion in May, a new record.
Sales in constant dollars fell 3.9 per cent in May, indicating a lower overall volume of sales.