Editor's note: The Chevy Impala is produced on the Oshawa "Flex" assembly line. An earlier version of this story misstated which version of the Impala is produced there.
DETROIT -- General Motors is trimming production at two of its car plants amid mounting dealer inventories, an effort to reduce stocks of the Chevrolet Sonic and Camaro, Buick Regal and other models.
This week, GM scheduled downtime for March 9-13 at its Orion Assembly plant in suburban Detroit, where the Sonic and Buick Verano small cars are made, to adjust supply to demand, according to a plant worker and another person with knowledge of the schedule.
The Orion plant also was idle last week and previously had scheduled a down week for April 6-10, also to trim excess inventory.
Meanwhile, the “Flex” line at GM’s Oshawa, Ontario, plant will be idled April 13-17, cutting production of the Camaro sports car, Regal sedan, Cadillac XTS sedan and Chevy Impala, one of the sources said.
The cutbacks come as car sales cool amid lower gasoline prices while demand for trucks and crossovers grows. Most of GM’s production trims are for nameplates that are well into their life cycles and due for redesigns within the next year or two.
Inventories on most of them have grown in recent months.
On Feb. 1, there was a 216-day supply of Sonics on dealer lots or on the way to stores, the highest inventory level since the subcompact debuted in August 2011, according to the Automotive News Data Center. The Regal had a 213-day supply, up from 96 days on Jan. 1. Camaro inventory was 131 days, up from a month earlier but lower than at the same time last year.
Inventory of the XTS (109-day supply on Feb. 1), Verano (92 days) and Impala (65 days) was not significantly higher than in recent months.
A GM spokesman declined to discuss the company's production plans.
GM executives have acted more quickly in recent years to cut production to avoid the heavy discounts required when supply outstrips demand, hurting profits and resale values.