GM has resumed production at five plants that had been affected by an 11-week strike at its supplier American Axle. The sites include the Oshawa plant in Ontario, responsible for the Chevrolet Impala and Silverado as well as the GMC Sierra, the Ramos Arizpe plant in Mexico, which builds the HHR wagon, and the Wentzville, Missouri, site that is responsible for the Chevrolet Express and GMC Savana vans.

Officials report the strikes had cost GM 230,000 units of production, with most of the models affected being its large pickups and large SUVs. Another 25 plants are still experiencing delays.

GM is still suffering from its own strikes at its Kansas City and Lansing Delta Township sites, which build the Chevrolet Malibu, Saturn Aura, Buick Enclave, GMC Acadia and Saturn Outlook. Analysts have said those strikes could be particularly damaging as sales of these vehicles are experiencing strong growth despite the U.S. mortgage crisis and rising fuel prices, reports the Detroit Free Press.

The General also made the announcement today that it would close its Windsor, Ontario, transmission factory in the second quarter of 2010 because there were no more products available for the site. About 1,400 hourly and salaried employees work at the facility making four-speed automatic transmissions for FWD vehicles. The strong Canadian dollar, higher labor costs and a movement towards six-speed automatic gearboxes contributed to GM’s decision to shut the plant.