Goodyear Tire & Rubber Co. said Friday it would close an undisclosed number of plants as part of a sweeping restructuring aimed at improving its North American tire business and saving up to $1 billion during the next three years.

The Akron, Ohio-based company, the world’s largest tire maker, did not say how many jobs would be affected, how many plants would be closed or their locations. But it did say it would focus the cuts on high-cost plants and increase sourcing from Asia.

Goodyear has a plant in Topeka, where it makes tires for large trucks and equipment – a market segment that has been busy, given ongoing U.S. military operations and emerging industrialization in China.

Earlier this summer, Goodyear said that all of the large tires it makes were spoken for through all of next year.